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Oral History Transcript — Dr. Lawrence H. Aller

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Interview with Dr. Lawrence H. Aller
By David DeVorkin
At Montreal, Quebec, Canada
August 18, 1979

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Lawrence Aller; August 18, 1979

ABSTRACT: Childhood; early interest in science (astronomy). Member of Astronomical Society of the Pacific, 1928. Special student at University of California at Berkeley, 1931, with Donald H. Menzel’s help. Regular student from 1932; comments on teachers and fellow students at Berkeley Student Observatory. Summer assistantship at Lick Observatory (Nicholas Mayall, Arthur B. Wyse), life at Lick Observatory. To Harvard University in 1937 for graduate studies; comparison between Harvard and Berkeley/Lick; teaching assistant at Radcliffe; 3-year membership in Harvard Society of Fellows, from 1939, of enormous importance for his development; works with Menzel and James G. Baker on the Theory of Physical Processes in Gaseous Nebulae, 1937; Analysis of the Atmospheres of the A-type Dwarfs Gamma Geminorum and Sirius based on data from Louis Berman; Jesse Greenstein. Comments on Harvard Summer Schools, Harlow Shapley’ s Square.” Volunteer teacher of elementary physics courses from 1942 at Harvard. Lawrence Radiation Laboratory, 1943-1945; work involved evaluation of the chemists and the Counting Group’s output from the electromagnetic separation process. Job offer from University of Indiana (Frank Edmunson) accepted due to cutback at Radiation Laboratory. Indiana years, 1945-1948, very productive (drafts for two astrophysics books); problems getting telescope time at Yerkes Observatory and unsatisfactory living conditions leads to acceptance of a promising tenured position at Michigan, a center with very active research due to Leo Goldberg; Robert McMath’s influence in the department; Keith Pierce and Aller’s work on infrared solar spectrum. Work performed at Mt. Wilson Observatory and Dominion Astrophysical Observatory. Goldberg resigns in 1959; comments on Aller’s decision to leave Michigan; discussions of funding; “over-head” (Aller’s talk at an AAS Meeting); comparison of Lick Observatory and Kitt Peak Observatory policies. Work at Mt. Stromio Observatory, Australia on sabbatical visits, 1960, 1968-1969, 1977-1978. Overview of opinions of the present state of astronomy. Comments on personal life, wife and children.

Transcript

DeVorkin:

Started the interview by asking about my early life and family background.

Aller:

I was born in 1913 in Tacoma, Washington. At that time my father was a printer. I had four older brothers hand a sister: They were close together in age but the youngest was 7 years older than I was. At that time my father was a printer, running a print shop on Jefferson Avenue in downtown Tacoma. He was a man of many talents and capabilities. Alas, his whole life was messed up with idles fixes from which no power on earth could uncouple him. By the age of 40 he was an established failure. This, in spite of the fact that he had great abilities in many things. He had gone to an agricultural college for a year or so and he knew a great deal about horticulture. He could have been a great success running a fruit farm; he was a marvel at that sort of thing.

He was literate, had read volumes of history economics, etc. The old man had two principal ids fixes: — one pertained to an apocalyptic assessment of the situation in which the world found itself. He anticipated imminent catatrophic wars, revolutions, and upheavals. The predicament in which the world finds itself today is probably not too far from that which he envisioned sixty—five years ago. The other idea fixe was that he was going to find gold, and that damn near wiped me out. That’s further down in the story. One of the tragic aspects of his life was that he insisted on expending his energies on things for which he had absolutely no competence, ability, or knowledge. He meddled in politics and wasted much time on it. His approach to gold mining was backbreaking and unrewarding. My mother had been a school teacher before she was married, They were both born in Mitchell County, Iowa, She was a voracious reader who had a respect for education and culture. My mother, Lena Belle, was a truly wonderful person. Education and culture were respected in the family but within, you might say a certain framework; some things were more acceptable than others.

DeVorkin:

What was your father’s full name?

Aller:

Leslie E. Aller. The given name, Leslie, possibly may have been part of his problem. If you give a boy a name that is usually a girl’s name, it may upset him, Shortly after I was born, World War I broke out, My father opposed the war. His perception of the situation was far in advance of the general public. He saw that the war was a very stupid affair, much of the so—called news was propaganda and he used to give speeches against it. His point was that the war was fought for commercial reasons. There is one reason for this war, three little words — “Made in Germany.” The reason for this war is competition for markets and access to raw materials. You are told to go out and die for the flag; you are really dying for the industrialists. (He spoke like Uncle Kees in Pierre van Paasen’s “Days of our Years”).

DeVorkin:

Did you recall him saying this after the war or do you have recollections from during the war?

Aller:

During the war I was very young. I knew that something terrible was going on in the world and I saw the soldiers marching off to war. I did not hear his public speeches during the war — soap box orations.

DeVorkin:

Was he running for political office?

Aller:

At one time he tried to run for Congress but had no luck. That was in 1918, I believe. There is one incident that must have occurred in 1919, right after the war and which I vividly recall. We were driving in the country in our Model T Ford. As we passed a corn field, the old man said: “See that corn over there. It will soon be ripe and the farmer will harvest it. I replied something to the effect that you raised plants to eat, didn’t you?” “Yes, but I want you to draw a lesson from this; just as that farmer raises corn as fodder for his pigs, so do the ruling classes of the world raise crops off young men to send them off to die for profit and plunder.”

DeVorkin:

Sound pretty eloquent.

Aller:

The old man was eloquent, but eloquence cannot paper over basic defects of character; viciousness, deceitfulness and irresponsibility. Except for my brother, Lee, who was closest in age to me, my older brothers were all trained as printers. They were successful at it. Leeon, the oldest, was the first to leave, He went to Olympia, finished high school, there and got married and completely escaped from the clutches of the old man. Lee was the rebel in the family. He ran off and joined the Navy, which infuriated the old man, All my brothers have related anecdotes illustrating the cruel, treacherous and vicious ways the old man treated them. His treatment of me was the worst of all. By 1922, he had decided to give up the printing business, let my brother Paul who was then 19 and my brother Louis who was not quite 18 support my mother and myself, so he could go off and look for gold. Paul had gotten a job in San Francisco and arranged for Louis to come to work in the shop. My mother and I left Washington State and sailed to San Francisco where we stayed from 1922 to 1925. He went off to the Beegum Creek area to look for gold. It is about 35—40 miles west of Cottonwood on California 36 and about 28 (airline) miles south of Weaverville. My mother and I stayed in San Francisco where my brothers Paul and Louis supported us.

DeVorkin:

How did you feel about this? How old were you now?

Aller:

When the old man packed up and left in 1922, I was not quite nine years old.

DeVorkin:

Did you take this very hard?

Aller:

I was upset by his entire pattern of behavior. Actually from March 1920 to June 1922, my mother, brother Lee (who was 14 in 1920) and I lived in a small place called Algona (now a suburb of Seattle). Paul went to San Francisco in 1921; Louis stayed with the old man in the shop in Tacoma and then went with him on his trip from Tacoma to San Francisco. The old man could really turn on the charm and overwhelm you with his eloquence. He had a hypnotic power over both men and women. Unfortunately, he could and did use his charm for thoroughly reprehensible purposes. He was the most treacherous hypocrite I have ever encountered in my life. With such an example before us, you might ask why didn’t we all wind up in the hoosegow? I think his behavior was so bad that when we rebelled, we rebelled against deceit, irresponsibility, treachery, and hypocrisy — and so we wound up being reasonably decent people. My mother suffered terribly from his cruel treatment of her; her diary attests to the fact it went on constantly. One of his ploys was to stir up trouble between siblings — which would cause our mother much anguish. In fact, I regarded my oldest brothers as sort of father figures, especially Leeon who was 14 years older than me. He succeeded brilliantly in spite of all the obstacles tossed in his path and raised a fine family. I want to outline this personal history before I talk about the science because without that you cannot understand the framework in which I had to work. So I will tell you the story in my order, if. you don’t mind,

DeVorkin:

Let me interject a few questions. One, when he went off to seek gold was there any resurgence of the gold fever at the time, or was this on his own?

Aller:

To my knowledge, there was no resurgence of the gold fever. For a long period of time he had wanted to look for gold. Tradition has it that his father, who a scout for wagon trains in the 1840’s found enough gold in California to go back to the Midwest and buy a farm. In 1925, the old man finally decided the Beegum adventure was not going to work and started to think in terms of other possibilities. Meanwhile, Leeon had taken a job with the Ketchikan CHRONICLE and wrote glowingly of employment opportunities in Alaska. Now the Alaska of those days was dependent entirely on mining, lumber, fishing and a little bit of tourism. Anchorage was a smaller town than Ketchikan! But the country was developing. Paul and Louis were enticed to go up there. Since my mother and I were dependent on my brothers, we jolly well had to go also. We arrived in Ketchikan in August 1925. The old man was not going to pass up this opportunity. He was go— ing up there to look for gold. Turning on the charm, he talked a local fisherman who was also a skillful navigator, into taking him on his boat when he went fishing. They’d stop in various places and my father would go ashore and examine the ore, He had taught himself practical analytical chemistry to a sufficient degree to run assays on the ores, as well as quickie blowpipe jobs.

DeVorkin:

Did he find gold?

Aller:

Yes, but it was in solid rocks and would take a million dollars to get it out. We were there only a few months before difficulties developed with the management of the Ketchikan CHRONICLE. My brothers were fired, so we all moved back to the states (Alaskans would now say the “lower 48”). My mother and I moved back to Tacoma where we stayed in the house owned by my sister and her husband. He was a welder but at that time they were in Santa Rosa. We lived in this house alone for about a year. My brother—in—law and sister returned to Tacoma late in 1926 and we continued to live with them until 1928 when they found the burden too great. Then my mother and I were shipped over to Seattle to live with Leeon and his family (October 7, 1928). The old man could not be coerced, cajoled, threatened, or wheedled into supporting his family, He had to go out and look for gold — and in the meantime my sister Jane and brother Leeon were stuck with the responsibility of looking after their mother and youngest brother.

Jane and Frank put up with it as long as they could and then the burden passed to Leeon. Finally, the old man found a bonanza, not gold, but the place to look for it at the extreme northern edge of California in the NE corner of Delnorte County not far from a little village, called Takilma — in Oregon. I remained in Seattle until July 11, 1929. By then I’d completed my second year of high school, At that stage the old man dragged me away from books and school to take me down to work as a slave laborer in his mining camp. At this time I was fifteen, In comparison with the experiences of many people in the world, particularly those who fell into the clutches of Hitler or old Red Joe or Pol Pot, my sufferings were minor. Nevertheless the misery was not negligible and my experiences are perhaps unusual among academics, There are two types of gold mines — hard rock and placer. In the former you dig out the ore, crush it, and smelt it to extract the gold. Our mine was a placer mine. You wash the mud down through what are called sluice boxes — in the bottom of which are placed slats, commonly called riffles. The theory is that the gold, being heavier than the silicates, settles into the riffles, Later you take out the riffles and pan down the mud that has settled to the bottom and which is supposed to contain the gold. Needless to say the process totally destroys the landscape. You have to wash all the dirt down to the bedrock, In theory you clean out the cracks in the bedrock very carefully, also, and recover the gold.

Of course you could not operate in this way at the present time, You could never get an environmental impact permit; they would wring your neck when they read the proposal. But that was more than half a century ago and mining had precedence over landscapes. Now, before undertaking an enterprise like that, any reasonable person would first raise the necessary capital to buy the essential equipment, lumber for flumes, pipes, and nozzles (called “giants” in the trade) so you would have the wherewithal to wash the dirt into the sluice boxes, The old man attempted to do this but the “investors” whom he lined up were crooks, who had the idea of getting control of the mine, selling stock to gullible clunkers, pocketing the dollars and absconding. It was just like a plot for a western and 1 wish I had time to describe what happened. They had a tidy little scheme to get control of the mine, but the old man was no fool and he saw through their trickery. Unfortunately, in anticipation of success the crooks sold phony stock to some trusting elderly people. This caused an awful lot of trouble and the old man damn near went to jail — which would have been a tragedy —— for in this instance he was completely innocent, These delightful events (which make quite an engaging story in their own right) occurred during the late summer and fall of 1929. By the time the old man had succeeded in talking the elderly would—be investors into grasping what had really happened and accepting the loss of their money — (the crooks escaped scot free of course) — all our money was gone and we were facing winter.

That winter was the nadir of my entire life, But the old man was determined not to let a little incident like that interfere with his id fixe. In August 1929 — a local sawmill operator, named Drews, was persuaded to lend very substantial help to building a dam across the creek, and supply lumber for a flume to conduct the water to a place where it could be used to wash away the ground into the sluice boxes. We had no pipe or giant so we just turned the stream of water onto the ground and eroded it away. So you either worked with a pick, shovel, and crowbar to assist the process or service the end of the sluice line where it jutted out into the raging river (I have a sketch of the whole layout — somewhere in my papers; it was prepared for a letter for my mother, but never sent because she came to the mining camp for Christmas 1929). My job during the winter of 1929—30 was to stand at the end of the sluice line where the mud came through, hopefully depositing the gold in the slots, But along with the mud came many rocks which could clog the boxes. I stood by the end with an iron rake, specially made for the purpose by Jack, the handyman who had cast his lot with us, I pulled the rocks out into the river which would take them away. All day I stood there, wading in icy water with leaky boots. During that charming winter, I was given to understand that we took out the magnificent sum of $17.50 for the season’s work — hardly an attractive income — even granting that it would now take more than $200 to buy what the $17.50 would then purchase. Now the old man had always preached that “I was going to starve to death monkeying around with astronomy”. Apparently he wanted to demonstrate what starvation would be like, We had some rutabagas and turnips from the garden — which had been pretty well plucked clean of all edibles by the deer. That was all the old man would provide and we would have been pretty well kayoed if it had not been for the “Care” packages sent by “good Comrad Ella”. She had come down to the camp to work as a cook, but when prospects got dim in the Fall of 1929 she went down to Napa and got a job in a restaurant. As her investment she sent these food packages that prevented total disaster, Other members of the family sent help when they could — but remember that the great depression was setting in at this time. The staple food consisted of rutabagas and turnips. A rutabaga is the most noxious vegetables that can be grown. It is not even fit for hogs. When it is cooked it produces oxalic acid, a poison that hits the thyroid.

It produces a form of myxedema or thyroid malfunction. It slows down your metabolism. Under starvation conditions this is one way the body can protect itself. At night I would sleep for ten hours, zonked out just like I had been drugged. Later on, when the miracle had occurred and I got to the university, I had a physical and medical examination, At least among students, the doctors had never seen a situation like mine. As a consequence of vitamin B deficiency in this starvation diet, I was afflicted with beri-beri which may have exacerbated the heart condition I had. If I ran or exerted myself markedly I started to gasp quickly for breath. Everybody told me that this symptom was simply because I was out of condition; if I exercised regularly I would get over the difficulty. This advice was not only nonsense, it was also dangerous, because my heart cannot handle the circulation problem. As long as I stay within my limits, I can get along all right. My son, Raymond, who is an MD calls this phenomenon “heart failure” — an inability of the heart to pump blood out at the right rate under exertion, It seemed to take the medics a long time to interpret the symptoms — half a century before I was told that I had an enlarged heart, sure sign of a serious defect. This affliction may have been produced by an infection when I was very young. Nobody would listen to me when I was a child. You can easily understand that under such circumstances being forced to participate in sports was a pure nightmare. One additional annoyance was that I have 3 diopters of myopia plus 3 diopters of astigmatism in my left eye, and 1 diopter of myopia and 3 of astigmatism in my right eye, so when I would look at a wheel all I could see were the vertical spokes.

With eyesight like that it may seem mysterious why I got interested in astronomy. Repeatedly, school nurses called my parents attention to my bad eyes, but the old man refused to do anything about it. Finally when I was 15 just before the old man hauled me off to camp, the Junior Red Cross bought me a pair of glasses. Suddenly, trees had leaves, and stars appeared as points instead of fuzz bobs. Defective eyesight can interfere with the development of motor coordination, and it certainly did not help my enjoyment of sports at school. Life in the mining camp only exacerbated my difficulties. As a consequence of starvation I was not in the best of health when I enrolled at the University of California on January 8, 1932. How that came to pass was the great miracle.

DeVorkin:

How did you get started in science — at the beginning, I mean?

Aller:

I think it goes back to what most impressed me when I was a kid. Remember, we were living in Tacoma, a city by the sea, not far from a great volcano, Rainier — which — in those days — was regarded as extinct, Transportation modes interested kids then as now and most of them, watching trains and boats, wanted to be locomotive engineers or sea captains. The sea mystified and terrified me, We frequently went down to the beach and one of the first things I noticed about the sea was that it was not constant. The tides would come in and go out; in Puget Sound they have high amplitudes, There was an awful lot of water moving and I could see it racing through the Narrows at great speed. “What causes the tides?” I would ask my parents. That bright object that you see in the sky at night, the moon! they replied. To me the mystery was how did the moon do it? It did not pull other objects on the earth, I could not feel the moon pulling me. How could it pull the water? Perhaps the clincher was the total eclipse of June 8, 1918. My father was a keen photographer who wanted to film the eclipse. He didn’t realize that you had to get into the middle of the track to obtain the best results and we went out to a point south of Tacoma, just inside the edge of the eclipse track. It was a miraculously clear day. I recall the sky getting dark, the sun disappearing, then suddenly a bright white ring around the dark disk, and it was all over almost in the twinkling of an eye. It made a tremendous impression on me because this phenomenon was discussed in the family as an item of great significance. All of these things happened circa 1918 when I was about five years old. The solar eclipse, the phenomenon of the tides which exhibited the influence of the moon attracting the seas of the earth, were two items that provided a great inspiration, Perhaps the 3rd item was a study of geography.

DeVorkin:

Was this in school?

Aller:

Even before I went to school my brothers showed me their geography books with accounts of strange lands, deserts, mountains, jungles, oceans and polar caps. So I strove to learn what I could about these distant places and developed a great ambition to travel, eventually around the world, After I’d been in school I saw a remarkable advertisement for the Grolier Society’s BOOK OF KNOWLEDGE, which clearly put across the fact that the earth was not an isolated planet with its moon travelling alone around the sun, but that there were other worlds circling the sun. The distances involved were staggering and the distance to the nearest star was beyond comprehension. It made a profound impression on me. This was about 1922 — at or near the time we went to San Francisco. Naturally, I wanted to get a copy of this book but that was out of the question. Alas, I had no access to a decent library, either. A critical event at this time was the Martian opposition of 1924, when Mars approached the earth more closely than it had for many years. In the newspapers and to some extent the classroom there was discussion as to whether there was life on Mars. The great thrill was a visit to Lick Observatory, September 13, 1924. This was really something — to get a chance to see a real observatory, a real telescope, and real astronomical objects through the telescope.

DeVorkin:

How did you manage to go?

Aller:

Certainly not through the graces of the Old Man. A friend of the family named Neil took my mother and me in a Model T Ford to Mt. Hamilton. We camped at Smith Creek on the way back. My mother was very much interested in all of this for she had wanted to see Lick Observatory for a long time. Unknowingly, she had exerted in influence in a very subtle way, which inspired an interest in astronomy. When she was a school girl in the 1880’s, the Lick Observatory was under construction. One of her teachers, whom she always referred to as Professor Chandler (not Seth C. Chandler), used to read to the students from a current periodical (possibly the Atlantic or Harpers) about the construction of a large telescope on a mountain in California.

DeVorkin:

This was when she was in Iowa?

Aller:

Yes, at that time she was still living in Osage, Iowa, She had wanted to study astronomy but it had been removed from the curriculum in her school just before she had a chance to study it. She was tremendously impressed by this account of the construction of the 36— inch and Lick Observatory and had a burning ambition to see it. Jupiter was the first object I ever saw through a telescope and I thought immediately it must be the most interesting object in the sky. In the 12—inch Alvan Clark refractor, under the conditions of good seeing that night the detail was absolutely superb. It is better than Saturn, even. Next we walked down the hall, I saw Mars through the 36-inch but it was terribly disappointing.

DeVorkin:

Did you know about the canals at that time?

Aller:

No, I did not. We will come to that later, One numerous incident might be mentioned. As we were leaving, I bought a little book, entitled A Brief Account of the Lick Observatory. The chap who sold it to me said “Study this hard and someday you’ll become an astronomer,” I never found out who it was, and there is no way of ever knowing —— but I followed his advice and I did become an astronomer. Fortunately, I did not miss any school in spite of our moving around — until I was fifteen and the Old Man yanked me out to work on his slave labor project. His attitude towards science was erratic, In principle he had great respect for education and studying so long as it did not interfere with his idees fixes. The Scopes trial occurred while I was still in San Francisco.

It was the principal topic of discussion at the dinner table, Every day the latest developments and testi— timony as reported in the papers were thoroughly reviewed at the dinner table. Darrow was the hero; William Jennings Bryan was the idiot villain. The Old Man was all for Darwin and evolution, although he never bothered to review for us the evidence (I learned that later when I took a zoology course in high school in Seattle 1928—29). Evolution was anathema to religious fundamentalists and therefore, as a militant atheist, he was all for it. As I mentioned, he learned a lot of practical chemistry all on his own. But he accepted uncritically a lot of junk, Ignatius Donnelley’s ATLANTIS. From time to time he would profess to believe in astrology — but he may have been faking it to torment me, As previously mentioned, we moved from San Francisco to Alaska in 1925 and then returned to the “lower 48”, but it was not until 1927 that I was able to get to a library in Tacoma and get some books on astronomy.

The selection was deplorable. Some were downright crank books, The only books by a professional astronomer were Percival Lowell’s contributions; the most interesting of these was “Mars as an abode of Life.” The first book I happened to read was Florence Grondal’s MUSIC OF THE SPHERES, It was about 8% astronomy circa 1925 and 92% pure fairly tales, but the fairy tales were delightful. Lowell’s books made a great impression on me, As matters turned out, I’m glad I read them, During the summer of 1928, I was down at the mining camp, This was a year before the Old Man pulled me out of school, I got the idea of writing to an old friend, James Fidiam, in San Francisco, I knew only his old address which turned out to be obsolete, but by the Grace of God and the US postal service, Fidiam got the letter and wrote back, telling me about the Astronomical Society of the Pacific. Alas I did not have any money to join at that time, From 1926 to 1928 we had been living in Tacoma, but my sister and her husband could no longer take care of us, so in October 1928, my mother and I had to go and live with my oldest brother, Leeon, in Seattle, On the afternoon of November 22, 1928, I went down to the Seattle Public Library and found on the shelf a very remarkable book — the second volume of Russell—Dugan—Stewart, ASTRONOMY. I took it home, smuggled it upstairs and started to read it. Gawsh, this was what astronomy was really about, By God, this is what I wanted to do. There was a lot of mysterious stuff about spectra and atoms and it was damn stiff reading. I cannot pretend that I understood it, but I tried to read through the entire book, trying to get the gist of what it was all about. The physics was tough, mostly unintelligible, but challenging and fascinating. Here were explanations of things I always wanted to know how you got the sizes and temperatures of stars, for example. It must be emphasized that I had to read the book on the sly. I would take it upstairs to my room and read it. Whenever I’d hear a step on the stairs, I’d ditch it and pull out the Spanish book I was studying for my classes. It was very hard to work under such circumstances, Hostility against my reading books on astronomy became sort of the official family policy; fortunately it was enforced only on and off and on basis unless the old man was around. My older brother was terribly annoyed that I was antipathetic to sports — “you should be interested in basketball” etc. etc.

They could not understand why I did not want to go out “and enjoy myself” - in fact being ridiculed and humiliated on a playground. Not bothering to inquire into my complaints about shortness of breath they regarded my behavior as aberrant when I told them point blank that I enjoyed studying science and detested being forced to go out and “play”. The Old Man did not care whether I liked basketball or not — preferably not as far as he was concerned, but astronomy books were anathema. His basic argument was that “I’d starve to death fooling with that stuff”. Of course from reading Russell—Dugan—Stewart, I realized that in order to do astronomy you had to know math and physics. If books on astronomy were interdicted, those on physics and particularly chemistry were not. One day, by chance I happened to be reading about optics in a physics book. The Old Man came by and said “what are you reading there?” Is that an astronomy book? Let me look at it,” I replied that it was a physics book I was studying. He examined it and replied. “Oh, well, it’s a good thing it wasn’t an astronomy book, or I’d have knocked your block off,” The official reason for the opposition was that astronomy was impractical that you could never get a job at such an exotic profession. My mother went along with the family dogma, but not emphatically as the others; she would say “Well, maybe you better study something practical; astronomy isn’t practical.” The clincher is that they were opposed to my studying astronomy but the Old Man was in fact not willing to help me get an education in ANYTHING! When the old man dragged me out of school, it was all for my own good (sic). The important and fundamental thing to note is that he would let nothing stand in the way of his pursuit of his own chimerical ambitions. He held those about him in disdain and contempt. My brother Leeon would have been glad to give me a chance as far as he could, In fact he invited me back from the mining camp, but the old man would have none of it. It is true that the old man did make some vague promise to the effect that when we got the mine “going” and the money was rolling in that I could go back to school, but I recognized this as one of his totally worthless promises. In 1928—29 at school I got no particular boost from my teachers, was taking zoology and occasionally talking to the physics teacher. They and the math teacher encouraged me to go on in science, In 1927 while I was still in Tacoma, my brother Paul bought me a telescope with a lens of 1—inch aperture. With this I could examine the moon, planets, and a few bright nebulae and stars, It showed the Galilean satellites but not the rings of Saturn, In 1928 I wrote to the astronomy department at University of Washington for some information on getting started in astronomy. The man who answered my letter and sent me some star charts was Herman Zanstra! He was temporarily at University of Washington.

DeVorkin:

Do you still have his letter?

Aller:

I may still have one of his letters but I don’t know what happened to it. When I met him some 25 years later, I showed them to him. He was amazed but he remembered me. In Seattle, in 1928 and 1929, I found myself in an environment where I could get library books —— even if I had to read them on the sly. Then, on July 11, 1929, I was dragged away and taken down to the mining camp, just in time to witness the attempted grab by the crooks and a severe deterioration of living conditions. In late September, my brother Paul sent me $3.00, a fortune. I “squandered” this money by joining the Astronomical Society of the Pacific. I was chided for not spending the money on some warm sox — it was not enough for a pair of shoes, at least the kind you would wear in a place like that. Now it is fortunate that the old man did not persecute me in the pursuit of my hobby. I kept the little 1—inch telescope and used it unobtrusively; the publications were not seized either. The Old Man realized he had the upper hand, and if I continued to dream about this stuff it did not make much difference. He had his attention focused on important things; the deteriorating economic and social fabric of the world and the impending Apocalypse. Both the leaflets and the publications turned out to be of enormous value, not only for the intrinsic information contained therein but for the fact that it enabled me to establish contact with folks of similar interests. Inspired by these leaflets I wrote to Seth B. Nicholson and Adriaan van Maanen who sent me books on mathematics and other materials. A. van Maanen arranged for a friend of his, Tod Ford, of Pasadena to send me Barnes “1001 Celestial Wonders”, and above all the marvelous volumes of l Du an and Stewart.

So at last I was able to do some studying on my own. The Telescope making volume listed names and addresses of several amateurs. One of them, a Canadian chicken farmer, who lived near Vancouver, A. R. Dunlop, was particularly helpful. He sent me a spectacle lens of about a metre focal length and a microscope eyepiece. I measured the focal length of the spectacle lens, cut a stick of appropriate length, mounted the lens by sewing it between 2 pieces of cardboard and stuck it on the end of the stick with thumb tack. Then I wrapped paper around the microscope eyepiece and secured it on the other end of the stick with thumb tacks. With this device I set it on a stump, separated the 2 components of Mizar, and saw for the first time the rings of Saturn. Dunlop also sent me the wherewithal to grind a mirror, and I actually started the job but before I finished, much more promising vistas opened up. I also built a spectroscope. My mother got a prism for me in Berkeley in the Fall of 1929. The old man had a camera lens which could serve as a collimator when mounted in a tube. When I pointed out to him that a spectroscope was a very valuable instrument for doing chemistry of alkalis, etc., he soldered 2 razor blades together to make a slit. Then I used the little one—inch telescope to view the spectrum — and by golly, you could see the D lines of sodium (unresolved of course) when I sprinkled salt in a candle flame. Also, I took the prism and held it in front of field glasses to look at the spectra of stars. They were difficult and disappointing, but I did notice one thing. The bright stars had colored spectra and the fainter stars did not — the well known rods and cone phenomenon. Also I tried naked eye observations of meteors. You have a chart — a flashlight and a stick. When you see the meteor, you hold up the stick to define its path among the stars, mark the track on the chart and note the time. I tried to work on sporadics, but very long time intervals were needed. Thus I was gradually working on this stuff, but I had to build up my background in physics and chemistry and I had to do it all alone, without any guidance. Del Norte County sent up some books on English literature, geometry (which I’d already had) and a simple physics book.

DeVorkin:

Weren’t there any child welfare rules that ———

Aller:

This was the Dark Ages of 50 years ago. My misery was not costing the State anything. On the other hand, if the old folks applied for medical help or welfare —— which would cost the state something, you can be sure they would track me down - no matter how badly the parents might have treated me, to try and extract all the toll they could. Valuable as were the leaflets, an even more important opportunity was offered by the Publications of the Astronomical Society of the Pacific. The August 1930 issue was memorable for its paper by Trumpler on “Absorption of Light in the Galactic System,” but my attention was attracted to a paper by D. H. Menzel entitled Hydrogen Abundance and the Constitution of the Giant Planets, speculating on the interpretation of the absorption bands in the spectrum of Jupiter. We now know these bands are due to ammonia and CR4. He had suggested that absorption bands produced in ice crystals suspended in an atmosphere primarily of hydrogen could produce the requisite spectral features. I wrote to him suggesting that under great pressure, hydrogen would be forced into the crystals and might modify the spectrum. Re responded to my letter and we struck up a regular correspondence which turned out to have very important consequences. It is one of the peculiar ironies of the situation that I got the idea about hydrogen dissolved in ice crystals from reading the spectroscopic discussion in one of the Old Man’s chemistry books. Menzel was busy but his letters were priceless treasures, He sent me an early Lick volume, containing Keeler’s classical photographs of nebulae — obtained with the Crossley.

These pictures showed for the first time what a reflecting telescope under good conditions could do and inspired the age of the great reflectors, I still treasure the volume. Among the astronomers to whom I wrote was Edison Pettit of the staff of Mt. Wilson Observatory. I asked him about thermocouples and I was quite impressed with the time and patience he took to write to me about how to construct one. Alas the technical requirements were far beyond the skills and arts available at a mining camp. THE BERKELEY DAYS Conditions never again got to be quite as bad as they were in the winter of 29—30 when we damned near starved, In 1930 and 1931 we had more successful gardens and were able to exclude the deer at least most of the time. Escape from the miseries of the ol’ Man’s slave labor camp came suddenly and unexpectedly. At Thanksgiving time, 1931, my brother, Paul, came up to the camp from San Francisco and talked the old man into letting me go down to the city with him for what was represented as a brief holiday, but which turned out to be little short of a miraculous escape, thanks to a lucky combination of circumstances, In the autumn of 1931 Menzel was teaching at U.C. Berkeley — on a brief semester’s leave from his normal assignment to Lick Observatory. I knew he was in Berkeley and when I arrived at my sister’s home in Oakland I called him up and arranged to meet him at the Students’ Observatory (later called the Leuschner Observatory). And so it came to pass that on the morning of the 30th of November 1931 I met Menzel. The events of that day are as clearly etched in my mind as though they happened only yesterday. From that moment on, everything was straightforward - not easy — mind you but possible. My sister was living in Oakland and it turned out that I was able to live with her and her family. Her husband, Frank, was a welder — a very generous and kindly fellow to whom I shall ever remain indebted, He’d been yanked out of school when he finished the 8th grade, but he appreciated the importance of education, Shortly after I met Menzel he suggested that I might like to come over the following week and try the final exam in astronomy I. There were ten questions of which I was to choose eight, but I’d never before had a choice in exam questions so I answered all of them, Since I’d studied Russell—Dugan—Stewart diligently, I was able to do reasonably well. Later Shane gave me a math exam in which I did not do very well, but at least I did not flunk abysmally. Menzel took all this documentation to Merton Hill, who was director of admissions to try to get me into the university as a special student.

Merton Hill was reluctant to admit me since they had a rule that a special student had to be 21, but Menzel evidently talked to him very convincingly because I was admitted as a special student and was admitted as a regular student in the autumn of 1932. It would have been a disaster to have been sidetracked for two years in a high school. Menzel returned to Lick in December 1931 and in 1932 he went on to Harvard. It was arranged that Professor A. 0. Leuschner, who was chairman of the astronomy department, would look after me. He was a wonderful fellow and a great astronomer of the old school, He had been educated in Germany, although he had been born in Detroit and he had many of the characteristics of a German professor but with one important difference. He took a great interest in his students. He gave me a job working in his garden at his home at the corner of Scenic and LeConte, about two blocks from the Students’ Observatory. Professor Leuschner was a man to whom I looked for reliable advice and for whom I came to have the most profound admiration, respect, and affection — but above all an enduring realization of deep gratitude. The Berkeley years were the years of the Great Depression. Many people had a much rougher time than I ever had, My sister and brother— in—law looked after me, but I still had to figure out everything down to the nearest nickel in order to get by. Survival demanded an exacting price. At school — emphasis had to be on grades, not just content, for in order to get a scholarship you had to get all A’s. It was not a matter of pride but a matter of whether you were going to eat or not.

DeVorkin:

Did you have financial assistance from Berkeley?

Aller:

At the beginning I had no scholarship but later I was successful although I nearly missed out. The clunkers at University Hall sent the notice to camp (which address I’d given them when I first came to town). Instead of forwarding this important news to me the Old Man suppressed the letter and I found out about the award quite by accident, but just in time to prevent its being withdrawn!

DeVorkin:

Did you take general education courses?

Aller:

Yes, I took courses in history, English, psychology, etc. History was fine; it is a subject I have always liked, but in English literature I got clobbered, We had an English teacher who knew the exact meaning intended by every character in Shakespeare’s plays in every one of said character’s utterances, Exams were exercises in divination because they required guessing these meanings and if you did not come up with the instructor’s interpretation you flunked, Needless to say I flunked, At the same time, there was a janitor in the observatory who used to lecture on the Bible while he scrubbed the floors, This man knew the exact meaning of every symbol used in the Book of Revelations, His discourses were fascinating. One day I reasoned to myself as follows: “Here are the 2 great classics of English literature, Shakespeare and the King James version of the Bible. The professor who holds forth on the first destroys any liking I might have for the subject, but the janitor who has to scrub floors gives inspiring lectures,” Phooey.

DeVorkin:

You had access to the observatory while you were an undergraduate?

Aller:

I was able to take course in observational astronomy, use a telescope for visual observations, use a transit instrument and do photography. Dan Popper taught me how to do astronomical photography; he was a very good teacher,

DeVorkin:

He was a graduate student there?

Aller:

At that time he was still an undergraduate.

DeVorkin:

Who else did you meet while you were an undergraduate?

Aller:

There was a very fine fellow there named Arthur B. Wyse, who was later on the staff of Lick Observatory. He was my first astronomy teacher and he had a very great influence on me. Poor Wyse was killed in a tragic accident in the war, while working on a submarine detection program. He would have gone far in astronomy I’m sure he would have become director at Lick and would have done a very distinguished job in that post. Nick Mayall was a graduate student at the time. Much later came John Albert Russell, Gerry Kron, and Horace Babcock, and many others. Among the students who were there when I arrived was an attractive young lady, Elizabeth Gillespie, who was betrothed to my best friend. She was a brilliant student with a warm, generous personality. Her sudden, poignantly tragic death from leukemia chilled all of us to the marrow. Berkeley’s students observatory was a congenial place to work. It was a refuge not only from the outer world but also from the rest of the campus. Also there was an opportunity to undertake special projects. One of the projects in which I was interested was getting the objective prism on the telescope into operation—determining the focus, exposure times etc. This was done under Professor’s Shane’s supervision. We had just completed the calibration in December 1934 when a telegram arrived announcing the discovery of Nova Herculis 1934, now called DQ Herculis. So we promptly went to work on the object and finally Al Mikesell, Dan Popper, and I published a paper on it — by modern standards we would call it only an abstract.[1] Mikesell went on to work at the Naval Observatory where he did a lot of work on polarization of starlight and instrumentation. All of us were undergraduates at the time.

DeVorkin:

Let me ask you about your training in physics. Since so much of what you do in your research requires physics, I’d like to know when you first became aware of quantum mechanics and modern physics, and its applicability to astronomy? Did you learn this in astronomy courses or in physics courses?

Aller:

Of course, I first became aware of the existence of atomic physics from reading Russell—Dugan—Stewart, but I learned these things in physics courses, and sometimes by reading books like Pauling and Wilson (Quantum Mechanics, 1935, Mc—Graw Hill). Alas, my background in physics was built up in a very spotty and haphazard way, Sometimes I did not get adequate advice from my mentors, but also some of the important physics courses were given at barbaric hours, as far as a practicing astronomer was concerned. To do classical astronomy what you really had to know was mechanics and a few elementary things about optics. The realization that you had to know electromagnetic theory as thoroughly as mechanics had not appeared. Thermodynamics was something chemists did and physical optics was a lot of fun but it did not have much to do with measuring star positions. These views seem so archaic now but you must realize we are recalling a generation of astronomers who were versed in orbit theory and astronometry pretty much to the exclusion of “speculative” topics. My physics teachers were mostly very good. Harvey White let me read his “Introduction to Atomic Spectra” 1934 McGraw—Hill in manuscript form in his office. I got interested in all kinds of spectroscopic problems. I recall the very first observations I ever got of a planetary nebula.

It was under the supervision of an engineer whose wife later taught astronomy at U.C. Davis. He pointed the telescope to acquire the spectrum of the object and said “Now, go ahead and guide on this object until I tell you to quit!” The objective prism plate was a success but I wondered at the time why anyone would worry about a few stray points of light when there were nice bright stars to work on. This engineer, Arthur Leonard, played an important role in the Eastbay Astronomical Society and later in the Astronomical Society of the Pacific. We need the expertise of more such dedicated amateurs. Somehow, though, perhaps as a consequence of reading White’s book, my curiosity was piqued by forbidden lines. One day while crossing the campus I saw J. Robert Oppenheimer. I knew that if anybody knew the answer to any physics questions, it would be he. So I said, “Professor Oppenheimer, I don’t understand why forbidden lines are strong in gaseous nebulae.” He forthwith gave me - on the spot — a lucid and perfectly correct explanation as to why these lines would be strong in nebulae but difficult or impossible to observe in laboratory sources. I always admired Oppenheimer. His mind worked with fantastic speed on all manner of things. Professor Leuschner suggested that “I take some work with Oppenheimer” so I went to the first lecture of his course called Introduction to Theoretical Physics. He breezed through particle dynamics in about twenty minutes and disposed of rigid body dynamics even more quickly: “Rotation is not a vector in the ordinary sense but an anti—symmetric tensor of the second rank. I’m sorry to cover all of these elementary things but we must do that in order to give continuity to the course.” Then he made a quick sortie into electromagnetism, asking the class to work out the Hamiltonian for the vector and scalar potentials of the electromagnetic field, I never went back.

The difficulty with the astronomy department in Berkeley was that it was so horribly ingrown. When I came there, all of the members of the department had been appointed up through the ranks. Leuschner had started the department. Then they had appointed R.T, Crawford and later Sturla Einarsson, then W. F. Meyer, and finally C. D. Shane. Later, Robert J, Trumpler came down from Lick to teach in Berkeley; he alone had not received his degree from U.C. Einarsson taught mostly elementary courses and least squares primarily for engineers. Shane and Trumpler were splendid lecturers. As for Leuschner, he was one of the worst lecturers I’ve ever heard, but an inspiring teacher, Why, because he brought into the classroom the true flavor of research. One day in the orbit class he announced: “A new object has been discovered that is moving very close to the earth (actually it was an Apollo type asteroid), Because of its proximity to the earth, we cannot apply the ordinary two—body theory that ignores every attracting body in the solar system but the sun,” We have to handle the earth’s attraction on this thing as it goes by. Then he explained what he called his “satellite theory” and how and why it would work. He got us all really enthusiastic about orbits be— cause we were doing something new - this was research. That is what made astronomy a lot of fun. His formal lectures tended to be rambling and obscure and sometimes downright terrible, but he would tell you how to look things up.

Crawford’s lectures were usually well organized, but tended to be burdened down with trigonometric transformations that could completely obscure what was fundamental. In other words the basic mathematical and physical concepts could become irretrievably lost in the search for convenient formulas for logarithmic computation. I went through every equation, some of it at the blackboard in front of the class where Paul Herget’s coaching saved me from total humiliation, but I never understood what I had been doing until I read the account in Moulton’s Celestial Mechanics. Einarsson was stuck with teaching the engineers. W. F. Meyer did the pioneer work on Beta Canis Majoris, a text—book example of Beta Cephei stars. He discovered several of the remarkable properties of this star but was so burdened with teaching that he had little time to do research or catch up on current developments in astronomy. Robert J. Trumpler was the exponent of the new view in galactic structure. In fact, he was the man who first recognized fully the existence and implication of interstellar extinction. His work on galactic star clusters was fundamental and played an important role in the development of ideas on stellar evolution. I had a course from him in galactic structure and statistical astronomy. He lectured with meticulous care in the dull monotone characteristic of people whose native language is French, but what he had to say was of very great value and interest. C.. 0. Shane was an excellent scientist and a very sharp thinker.

He was a man of very great ability and of enormous administrative skill. In 1936, which was the year in which I graduated, he suggested using some spectrograms he had obtained with the slit spectrograph at the Crossley to get some eye estimates of line intensities that could be compared with predictions of a theory that had been proposed recently by the Dutch astrophysicist, Pannekoek, Laurence G. Stoddard, who was then also a student in Berkeley, and I undertook this task, The spectrograms covered the Balmer jump. Pannekoek’s theory, which pre—dated the discovery of the negative hydrogen ion as a source of stellar opacity, predicted sharp increases in line intensities shortward of the Balmer limit as you went from early A—type stars to C stars. The eye estimates of intensity, crude as they were, sufficed to show that stellar spectra did not follow Pannekoek’s predictions. In cool stars the opacity remained high beyond the Balmer limit. We now know of the dominant role of the negative hydrogen ion in continuous absorption in cool stars, but in 1936/37 the discrepancies were puzzling..[2] In 1936, just as I was finishing my last term paper before my graduation, my eyes went bad on me. For several months I was unable to read or work. I believe it came about because I was working very long hours, eating cold food all the time, and was under constant strain. Fortunately, the affliction gradually faded away when I got proper medical attention. It is fortunate that I’d not planned to go to Harvard that year, or I would have gotten off to a very bad start. I took one year of graduate work before I went on to Harvard, spending the academic year 1936/37 at U.C.

DeVorkin:

Would you have accepted any other graduate department or was Harvard the place to go?

Aller:

Harvard was the place I wanted to go because I wanted to work with Menzel. I liked Berkeley, but even in spite of Professor Leuschner’s enthusiasm, I could not get all that worked up about orbits — especially when you had to compute them by logarithms! There was one incident that gave the final small nudge: Crawford gave a course on the satellites of the solar system. It was concerned mostly with measuring their positions, calculating two—body ephemerides and finally something about mutual perturbations. On the first day, he wrote down the data for eight satellites of Jupiter. Somebody in the class (not I) said “But Professor Crawford, there are nine known satellites of Jupiter.” “Well,” said Crawford, “when I had this course from Hermann Struve in 1912, there were eight satellites,” and went on lecturing. That’s not the punch line. The 9th satellite was discovered by a graduate student from the Berkeley astronomical department, Seth B. Nicholson, who went to Lick and found it with the Crossley.

After that, I went down and sent a telegram to Menzel: “Can you find me a position at Harvard.” It is important to point out that I would have gone anyway — as long as I had a fighting chance to make ends meet. This turned out to be a tough problem that required lengthy discussion, The Harvard offer did not come through until the morning of April 15, 1937 — the deadline for accepting offers. My telegram of acceptance arrived just in time in Cambridge. In recalling my experience in Berkeley there is one thing I want to emphasize. All of the staff there; Leuschner, Meyer, Crawford, Einarsson, Shane and Trumpler extended to me a helping hand, each in his own way. I was a brash and tactless yokel, who out of carelessness or naiveté, did many things to vex them. Their patience must have been tremendous, In spite of all these irritations, they all wished me well. THE LICK EPISODE In may 1937 I went up to Lick Observatory as a summer assistant. I had the extraordinary good luck of being assigned to work with Nick Mayall who was measuring the radial velocities of star clusters with the Crossley. Later I worked with him on the rotation of the spiral galaxy Messier 33.[3] In many respects I think that was the finest research project in which I was ever engaged. This galaxy is tilted by a small amount; it is not face—on like MlOl. We started the M33 project in the late summer of 1938 and completed it essentially in 1939. The observations were difficult because we had to take very long exposures, sometimes amounting to two nights. By orienting the spectrograph it was possible sometimes to observe two objects on the slit, but at the severe price of having to literally walk the plank all during the second half of the night. It is miraculous that nobody got killed down there. There was a stairway up both sides of the dome beside the shutter, so you put the plank across on the stairway and crawled out on it like a raccoon until you would look in the eyepiece. We were able to, observe about 17 nebulosities and measure their radial velocities, thus obtaining the rotation curve of the spiral as defined by these HII regions. Thus we were able to calculate the mass. There was one other aspect of the M33 work.

We took a series of exposures of the comparison arc with an iris diaphragm which enables me to make a series of calibrated eye estimates of the intensities of the emission lines in the various nebulosities, To my surprise, I found that the excitation of these nebulosities varied with distance from the nucleus.[4] Such changes have been found in many galaxies and are generally interpreted as coming from a change in chemical composition of the material with distance from the nucleus, but in the 30’s such an idea would have been anathema. In the summer of 1937, though, I was working with Mayall on the radial velocity program for star clusters, Most of them were easy, but some were relatively difficult, Nick Mayall was very patient with me. He was an absolutely superb observer — he knew how to squeeze the last quantum out of a telescope. He was meticulously careful; his skill was vividly illustrated to me by his work on M33. Mayall had direct photographs of this spiral taken under conditions of very good seeing and he had an acute eye for picking out fuzzy spots. (We would not do things that way now, We would use an objective prism with a Schmidt — or a narrow band pass H alpha filter, but that was not practical in the thirties), He made very careful charts and decided where to set the slit; he would set me up on the objects, centering them by looking through the slit jaws.

If it was a two—night exposure, I’d run the night until I could see the first trace of dawn, then pick it up on the second night and finish it off, The mounting was such that during the first part of the night you rode the platform. That was nice and comfortable, but when the object crossed the meridian, you had to turn the dome through 180 degrees and the eye—piece was now away from the platform. Then one had to put the plank across the stairs and crawl out on the plank to look into the eyepiece. As the telescope got lower and lower in the west, the eyepiece got harder and harder to see. You had to bring the plank close to the telescope and that meant shimming it with blocks or books. Observing was exacting in those days. Now, with a large instrument you sit in a warm control room and watch the image on the TV screen. That is the way it should be done. But on the other hand, in the thirties we had nice dark skies at Lick — one cannot now take more than an hour’s exposure with the same instrument. In 1937 I also did some work with Arthur Wyse who had taken slitless spectrograms of stars of the north polar sequence in an effort to find what effects the Balmer jumps would have on photographic magnitudes. The question had been raised by Seares who found that the magnitude sequence changed when they used aluminum coats. There was a large collection of spectrograms, of course — nearly all radial velocity plates.

My attention was directed to the variable radial velocity of the supergiant, Deneb, I studied the spectral line intensities and found that over the range covered by the Mills spectrograph plates, there were no changes, doubtless because I was confined to using lines of ionized metals. Later I was able to combine these with other data and find some suggestions that different ions might follow different curves of growth in a supergiant atmosphere, but the results were not convincing.[5] Also in 1937 they had invited Ejnar Hertzsprung to come to Lick Observatory to observe double stars. When he arrived, he found that, unlike with modern telescopes, you could not set the 36—inch exactly on a position. You had to have finding charts and I was giving the job of tracing them by hand from the BD charts. I don’t know why they did not copy them photographically, but the director decided I was to make the charts. Of course, I was terrified that I might make an error so I did the whole thing over twice on different days. Hertzsprung was a very intense person whose sole interest was astronomy and if you could draw him out he had very interesting things to describe. But he was not a man to whom you could talk casually; he was the last man in the world to whom I would mention any personal problem. I never received any complaints about the charts, nor praise either. Thus, I worked as Hertzsprung’s assistant (although briefly) but Henry Norris Russell was a personal friend. The contrast between these two men was enormous.

Hertzsprung’s interest was intensely focused on astronomy; Russell had a wide variety of interests, history, archeology, mineral resources — all sorts of things. Russell was a charming conversationalist; Hertzsprung would appear ill at ease on those rare occasions when I saw him at a social gathering. There were certain aspects of life that were less than idyllic at Lick. The Observatory had been founded in the 19th century on what was then a relatively remote mountain top; its first director was the autocrat, Holden, who ran the place as though it were a fort in hostile territory. He established the firm tradition of the despotic director. Keeler, who succeeded him was a humane, decent person but he did not live long enough to make any substantial change. Campbell brought with him the Scotch tradition of discipline and under his regime you still had to ask permission to go down from the mountain. Aitken took over the management of the observatory when Campbell became president of the University of California and the restrictions were gradually relaxed. By 1937, you only had to tell the office you were going down — a reasonable request at an isolated spot, McLaughlin told me the following (possibly apocryphal) story about the Campbell era: “Once upon a time a student at Lick Observatory was giving a friend a tour of the place. He showed him the telescopes, the transit instrument, the library, the clocks, and explained the nature of life there and what they did, and the rules under which they operated. When he finished, the student asked if there were questions “Yes,” asked the visitor, “where are the gallows?” All of this I understood before I went up there, but there was another aspect, the attitude of the people on the mountain towards newcomers.

I was quite unprepared for the hostility I encountered in certain quarters. I received authentic reports of malicious gossip being circulated by people who had never met me, Perhaps it was due to an inherent spirit of elitism, The director, William H. Wright, and some others believed that astronomy should be the exclusive preserve of those who are the cream of society, such as children of ministers of the gospel, the wealthy, and the well—born, If one is so unfortunate as to come from a working class family, you should be content to stick to your lot, They knew about me, of course, with my background that would have supplied at plot for an Horatio Alger novel. To the elitists I was only proletarian scum, One afternoon I walked down to the Crossley to open the dome so as to equalize the temperature for the nights work, I saw Director Wright watering his garden. He had joked at me on occasion, so I asked him how he liked his new job or words to that effect, After a long silence he turned on me savagely and said: “Somebody ought to tell you to maintain the proper respect for your superiors. If I or any member of my staff wishes to joke with you that it his right and privilege, but at all times you should show proper respect and not make any wise cracks!” I apologized on the spot for my bad manners and assured him it would never happen again. Although I took great care never to incite his wrath, I’m not sure that it did me any good, For I’m sure I was on his black list. Years later, Menzel told me how in response to a favorable remark about me, Wright broke forth into a torrent of scurrilous comments. In the beginning, Wright was more charitable in his views and actions; it was later that he tried to black—ball me at Mt. Wilson and I do not know how many other places, My difficulties were exacerbated by the observatory secretary, Leslie C. Potwin, who took a dislike to me for some reason. One anecdote should suffice, In 1944 while I was doing war work in Berkeley, my wife and I went up to. Mt. Hamilton for a brief visit, Our son, Hugh, who was 2 years old had had a long bout with pneumonia and other infections so somebody had to hold his hand when he walked, Potwin observed all of this and Freddy Leonard of UCLA reported her evaluation. “Oh, yes the Allers were up here with their idiot son!” Hugh is now associate professor of astronomy at the University of Michigan and in charge of the radio observatory. I’d hate to give you the impression that all or even most of the astronomers at Lick were like that, but you do not need very many malevolent characters to cause trouble.

There were some fine people at Lick. I recall my first meeting with Aitken in 1933. He was still director then. At the time I was taking an elementary observing course; there were 3 of us working together — a business major named Crawford, a mathematician McCune, and me, We drove up in Crawford’s car on a visitors night and hung around until all the other visitors had left. We did not relish the idea of driving back down the road, which had a turn for every day of the year, at night. We had blankets etc. and wondered if there was a place we could snooze until morning. Wright appeared and said if he had to make the decision it would be no, but he was not yet the director and Aitken, who was coming up to measure double stars, would settle our fate. I’d never met Aitken before, We explained who we were and that all we wanted was a place to spread our blankets. He replied that camping was forbidden, but if we did not build a fire we were not technically camping, and we could sleep overnight on the floor of the schoolhouse. And so we did. Aitken was a fine fellow and a good astronomer, although he had no feeling for, or appreciation of theory. George Paddock was a spectroscopic observer at Lick; he was an expert on spectrographs, their care and adjustment. He was always considerate of other people and concerned about the students. When the nights were longer, I used to get very tired and sometimes I’d just sleep through lunch. Normally, if you did not get to the table on time, that was your hard luck. I would stagger out of my bed, bleary—eyed at 2PM and find a little package on the doorstep, courtesy of George Paddock. He looked after every student this way. When he noticed an observer missing, he would go out to the cook and say “so and so isn’t here; he worked last night — please prepare a sandwich that I can take up to him.” On Sundays we would go on hikes, He knew the Mt. Hamilton area intimately; some of my most treasured memories of Lick days are of hikes with George Paddock.

Another chap who was very good to the students was Fritz Neubauer. He’d let you know when he was going to town so he could get things you might need, e.g., toothpaste. Fritz and his wife would invite students to his house for refreshments on Sunday afternoons. These people were despised by the elitists. Joseph H. Moore was associate director under Wright. He was a warm, likeable fellow and he knew a whopping lot of practical things about spectrographs, observing, and photographic plates. He went out of his way to enable me to work on my research programs during the war. Hamilton Jeffers brother of the poet Robinson Jeffers, was interested mainly in positional astronomy and double stars. He was courteous and considerate to us students. Gerry Kron was still working on his thesis at the time, developing a photoelectric photometer. He was an expert experimentalist and I was glad to see that he was appointed to the staff. There was one hobby that I pursued on Mt. Hamilton, looking at Mars with the 12—inch telescope. Although the Martian opposition of 1937 was not as good as that of 1924, it was still a favorable one. My curiosity about the alleged canals of Mars had been piqued by reading Lowell’s books ten years before. Now there was a chance to see for myself. Larry Stoddard and I used to go up and look at the planet and we each made drawing of what we saw. I’ve saved these drawings (but they were never published) and have compared them with those by deVaucouleurs. Our sketches were very similar. When the seeing was good, I could see many details on the planet. The better the seeing, the less did anything look like canals. At no time was I able to see anything resembling a canal, One Saturday evening, G. Wesley Palmer (another graduate student) and I were looking at Mars through the 36—inch just as the last visitors were leaving. Neither of us could see any canals. Just when Trumpler arrived to start some spectroscopic work. He looked through the telescope and remarked: “Yes, there are several canals. I can see four or five of them running around the planet.” Try as hard as we could, we simply could not see them. But it is fortunate that I made those drawings of Mars; they were to pay off in a rather unexpected way. THE HARVARD YEARS

DeVorkin:

You have mentioned your decision to go to Harvard, but now you are really leaving your family.

Aller:

Yes, it was a hard decision to leave Berkeley where things were comfortable, and go to Harvard where I was betting on the unknown,

DeVorkin:

You could have stayed at Berkeley for your PhD?

Aller:

That is correct but I don’t know how well it would have paid off. Except for Trumpler and Shane, the background of the people there were pretty well centered in 19th century astronomy. At Lick, Wyse and Mayall were certainly up to date and experts in their fields, but there was no place where you could get training in theory. I left Lick in early August 1937, travelling up the coast to visit my parents at the mining camp and thence on up to Seattle and Victoria. At the suggestion of Mrs. Leuschner I planned my journey over the Canadian Pacific with a stop—over at Yerkes Observatory on my way to Harvard. When I arrived in Victoria, I found I could get a bus to the bottom of the hill below the Dominion Astrophysical Observatory. I trudged up the hill carrying my suitcase and briefcase which Professor Leuschner had given me as a graduation present. Here I found C.S. Beals, whom I’d met one evening at the Crossley. He greeted me like a long—lost friend. I was greatly impressed with the hospitality of these Canadian astronomers. Here I was, an unknown graduate student— at the first rung of the academic ladder — walking in on them unannounced, as yet they treated me just as though I was a distinguished astronomer. I got a chance to talk with Dr. Beals about his work on Wolf—Rayet stars, I don’t recall the details of the conversation, but I’ve been interested in WR stars ever since. Also I had discussions with J. A. Pierce and Harper about some of their investigations. The following day I stopped in Vancouver to meet A. R. Dunlop the amateur astronomer who had helped me so much in my years at camp. My next astronomical stop was at Yerkes Observatory, where my good friend — Gordon Wares — was then a graduate student, Here I met Director Otto Struve, who was very cordial and courteous and took Wares and me to lunch and talked about the work of the observatory. Here I met a promising young theoretician, Louis Henyey, and a handsome, youthful Indian, S. Chandrasekhar, whom I was to see often in the years to come. The Yerkes Observatory impressed me as a very active center of research. On the evening of September 17, 1937, Menzel met me at old South Station in Boston and took me to Harvard College Observatory where I met Leo Goldberg, Bart J. Bok, and Harlow Shapley.

DeVorkin:

What were your first impressions of Shapley?

Aller:

I thought he was a very energetic and intense person, a very fine chap in whom I felt I could have complete confidence in personal matters,

DeVorkin:

Was there any question that you’d be working with Menzel or that you might be working for other professors?

Aller:

Of course, I’d come to Harvard particularly with the idea of working with Menzel. Certainly, that did not exclude the possibility of working with other people on specific problems, but my main interest was in what Menzel was doing on stellar atmospheres and gaseous nebulae. He started out by giving me a stack of notes and a reading list and said “This is your assignment. Read these and tell me what you think of them. We will go on from there.” So my work with Menzel started out on a rather informal basis, although I did attend his lectures and those of other professors. Life at Harvard was a lot different from what I’d experienced before (I’ll go into more detail later), An old high school buddy from my 1928/29 days at West Seattle High School had travelled through the Canadian Rockies with me and had come to do a year’s work in engineering. We found a room together, near the law school, but not far from the observatory. My whole routine was different now and I was on a very tight budget. A welcoming speech in old Memorial Hall by Harvard President Conant did not make me feel any better. The only passage that stuck in my memory banks was: “Many of you will not make the grade. Here you’ve spent a year learning that you can’t be, say, a chemistry professor. Don’t regard the year as wasted. It will have been a very valuable experience to you!” To which my reaction was “ugh” what a cheerful beginning! The comparison between Harvard on the one hand and Berkeley and Lick on the other, at that epoch was interesting. At Harvard there was active discussion of everything of significance that was happening in astronomy. There were lots of ideas floating around; numerous engaging research proposals were to be picked up just by keeping your ears open. Theoretical ideas were bandied about and criticized. Whilst in Berkeley, only Trumpler at the time was engaged in a full—time research effort, here everybody had some kind of a research project and some people had several. Discussions were stimulating and exciting. When it came to the instrumental wherewithal to carry out research projects, the situation then was quite different. At Lick you had efficient, beautiful instrumentation and although the telescopes were small by modern standards they were placed in what was then a good site and operated well, At Harvard they had a number of photographic cameras, a 24—inch reflector and a 61—inch reflector, They had objective prisms but no spectrographs. To an aspiring spectroscopist, the situation was patently deplorable. Coming as I did from work with the Mayall nebular spectrograph on the Crossley, I immediately saw that if I was going to do a spectroscopic thesis on gaseous nebulae, I’d have to sneak back to Lick and get the data. Fortunately, I was able to get to Lick in 1938 where I again worked as Mayall’s assistant and was able to get the plates for my thesis, Some of them got damaged in the mails and had to be repeated. Since then I’ve trusted very few plates to the mails, Fortunately, Wright let me work at Lick in 1938 and 1939, and Menzel had no objections. In fact he thought it was a good idea.

The only person who raised any question about it was Shapley. “Why is Aller running off to Lick; he’d better stay here and work on his thesis,” To which my reply would have been: “With what?” One of the graduate students there had put together a combination of a poor replica grating and some lenses together with some bits and pieces lying around the observatory to produce what was intended to be a spectrograph, all for a total outlay of ten dollars, Well, it behaved just about the way you would expect to have a ten dollar spectrograph behave. I wasted ten nights at the Agazzis station and gave up in despair. Shapley seemed to have no appreciation of the importance of good spectrographic equipment. Of course he was not a spectroscopist, and it never seemed to have occurred to him that good spectrographs were essential. In frustration, I once made the comment “with Harvard ideas and Lick observations you could do some great things in astronomy.” Think for a moment — can you imagine a more undiplomatic remark. In the fall of 1937 I started to work with Menzel and James G. Baker on the theory of physical processes in gaseous nebulae. Menzel and Baker had already solved the problem of the Balmer decrement, so we turned our attention first to the problem of radiative equilibrium and energy balance, deriving the relationship between the electron temperature of the gas and the energy distribution in the exciting source, taking into account energy losses by recombination, free—free emission, and collisional excitation..[6] Results similar to those we had found were derived some eight or ten years later by Spitzer who considered only the continuum while we had considered bound levels as well. Later we worked on the transfer of radiation in the continuum.[7] We worked very long hours and very hard on the problem. It was a lot of fun. Baker was just getting started on his splendid work on optics then. I think he originally wanted to do a thesis on line intensities in stellar spectra; he had worked with Menzel on the latter’s formulation of the curve of growth (1937). Shapley directed him to design his own spectrograph. He started out to do this, became so interested in optics that he directed all his efforts into that field. Jim never returned to his original thesis topic, but he went on to make enormous contributions to optics. The last paper on which Baker collaborated with Menzel and with me pertained to theoretical line strengths of forbidden lines.[8] It was written in collaboration with George Shortley. Thereafter he was deeply involved in his optical work. The observations which I obtained in 1938 and 1939 provided data for further papers on the interpretation of the spectra of gaseous nebulae.[9] We estimated the electron densities[10] from the intensity of the continuum at the head of the Balmer series, and the electron temperature from the ratios of intensities of the forbidden lines of (0111), making use of target areas for the collisional excitation of metastable levels as calculated by Menzel and Hebb. These cross—sections were actually too large but the ratios were not too inaccurate and in fact led to electron temperatures that were smaller than, but not too far from currently accepted values.[11] We also used the target areas to estimate the concentration of O ions and showed the influence of collisional cooling in the establishment of the electron temperature in gaseous nebulae.[12] During the interval from 1937 to 1939 I had been living on what you might call a shoe string. I had a grant from the Dean’s office which amounted to free tuition. So far so good, but you have to live. I got some money as a teaching assistant at Radcliffe and a grant from Shapley 1937/38 that enabled me to make ends meet. The following year I got what was called a Parker Fellowship.

This was described as a very fine fellowship and indeed it was by the standards of those times. The curious fact, though, is that financially I was actually worse off than I’d been during the preceding academic year, because the Parker Fellowship paid less than the tuition scholarship from the Dean’s office added to the grant from Shapley. Though I might have gained in prestige, I’d certainly lost ground economically. I was working on a very narrow edge and had to figure things down to nickels and pennies in order to get by. I didn’t have the foresight of my roommate, who borrowed money and piled up a huge debt, which he later paid back in inflated currency after the war. Certain contrasts between Berkeley and Harvard were striking. In Berkeley there were many students who were not well off; you could be a pauper and still be an intellectual. You could be poor and still get an education. If you were a resident of California, you paid $52.00 per year in general fees. You could even go to graduate school on a shoestring. In the East only those who were fairly well fixed financially could get an education. I found myself in the peculiar position of being in the community but not of it, In other words, the level of my education and intellectual predispositions corresponded to that of a member of a financially secure class, but my economic status was more closely akin to that of a mill hand.

DeVorkin:

Did other graduate students fall into that category with you?

Aller:

No, I was the only real pauper in the bunch,

DeVorkin:

Who were your contemporaries?

Aller:

Besides Jim Baker and Leo Goldberg, there were Donald MacRae, the Canadian astronomer who later -became director at Toronto, Rod Scott, who went to work for Perkin Elmer, Jim Cuffey who was at Indiana for many years, Shirley Patterson from Canada, and Edith Jones Woodward. My economic situation improved spectacularly in 1939. Menzel nominated me for membership in the Harvard Society of Fellows, Thanks to his efforts and those of Shapley, Bok, and my physics teacher VanVleck, I was accepted. The sponsors wrote letters of recommendation, supplied documentation, and testified in person. The last step was a personal interview. You can imagine what a grueling experience it must have been to be marched into a room to face the committee and answer their questions. The chairman was a tall, dignified, bewhiskered scholar, Dr. L. J. Henderson who had moved from medicine to sociology; he clearly dominated the group.

There was an English professor by the name of Lowes, an authority on Keats, a charming, humorous theologian, Alfred Darby Nock. Morrison —— the historian who wrote on the voyages of Columbus, the great philosopher and logician, Alfred North Whitehead, elderly, bowed who fixed an intense gaze on me as I walked in the room. And finally, there was the man who had grubstaked the whole deal, A. Lawrence Lowell, President Emeritus of Harvard, and a kid brother of Percival Lowell. There were some general questions on what I wanted to do and what I thought was important in astronomy. They asked questions about the material that had been submitted on my behalf — which included the drawings of Mars and it was on this subject that Mr. Lowell led off.. Had I seen the canals? No, but I thought that Mars was worth studying and I intended to continue these observations if I had the opportunity. It turned out that this is what the old fellow wanted to hear. The controversy over Mars had adversely affected the astronomical community and there was a kind of a consensus that if you had any sense you avoided the subject. Here was a young fellow that believed that Mars was worth studying. That seems to have been what was important. The Society of Fellows was Of enormous importance in my life. Most obviously, it meant that the severe poverty under which I had lived for so many years was now banished. But it was not the end of worry, for my appointment in the organization coincided almost to the very day with the outbreak of the Second World War.

To the boy from the mining camp, it was an entirely new world, different from that of the astronomers who lived in their observatories and the physicists who slaved in their labs. In addition to the committee that met me, that constituted the senior fellows, there were about two dozen young junior fellows, most of them younger than me. We all met together on Monday evenings; the junior fellows lunched together on Tuesdays and Fridays at Eliot House. They were drawn from different fields; there were linguists who were experts on the literature of strange peoples, medievalists, classic scholars, sociologists, medics, biologists, logicians, chemists, physicists, and astronomers (Jim Baker and myself). Our discussions and arguments were fabulous, since we lived in different worlds, in the framework of quite different concepts and traditions. You learned to respect’ people who had opinions widely different from your own. My three years in the Society of Fellows did more for my education than any three years before or since. Among the junior fellows was Woodward, later to become Nobel Laureate in chemistry. There were many more who were later to occupy distinguished positions in academic circles and even in industry. The experiences and anecdotes of the senior fellows were particularly interesting. It was a thrill to listen to Alfred North Whitehead describe how he, as a young student, sat beside George Darwin listening to the lectures of John Couch Adams, co—discoverer of Neptune in 1846. Adams would develop long expressions for planetary perturbations and Darwin would ask which of these terms in the series expansions had been observed. Adams would reply that he did not know and furthermore he did not give a damn. But the most interesting of Whitehead’s anecdotes and one that I was to remember many times was the following: It seems that there was a competition for a fellowship at Cambridge. There were two finalists. One submitted a lengthy document, like unto a Sears and Roebuck catalog in thickness. The other submitted a very short essay, but one which Whitehead noticed contained a number of interesting ideas. The committee wanted to give the fellowship to the verbose applicant, but Whitehead argued long and hard in favor of originality and finally won over the committee to his point of view. The fellowship was given to the man with the short original essay. The verbose writer disappeared from sight and was never heard of again.

The successful applicant was Arthur S. Eddington! You met so many chaps who were experts in such diverse fields that you began to grasp the vast range of academic experience and the incredible intellectual wealth of civilization. As I look back on the experience, I think that I entered the Society of Fellows as little above the level of a barbarian and left it with a vision of the vast cultural jewels of the western world. It was customary among my predecessors in the Society of Fellows to spend their summers in Europe, but since I joined the organization and was placed on the payroll the day the European war got rolling, things were quite different. The days of my membership coincided with the darkest hours of the Second World War, Pearl Harbor and the battle of Stalingrad. The term in the Society of Fellows was intended to give the lucky junior fellow three years freedom from worry —— with a chance to pursue his own interests. Some had six years, but I was not eligible as I’d passed my 25th birthday when I won the fellowship. It made little difference because of the war. Even so, those few months that were available to me before the darkening war clouds directed attention to other things were of enormous value. I worked on the analysis of the atmospheres of the A—type dwarfs gamma Gerinorum and Sirius by curve of growth methods[13] Louis Berman had sent me much data from the Mt. Wilson files for the spectrum of Sirius. Many were experimental plates; some were taken with gratings with a lot of scattered light, and some were of excellent quality. The Germinorum data were supplied by Greenstein from the new spectrograph at McDonald Observatory in Texas. I tried to apply the state of the art theory of hydrogen line broadening, f—values etc. and derive atmospheric parameters and determine chemical abundances. It was or of the first detailed applications of Menzel’s curve of growth to stellar spectra. Then making use of the observations of the lines in the near UV spectra of planetary nebulae that I had obtained in 1938/39 at Lick, Menzel and I made the first attempt to give a quantitative theory of the Bosen fluorescent mechanism for lines of 0111. We concluded that to within the limits imposed by the accuracy of the observations, Bowen’s theory met the test.[14] Since then, many studies have been carried out.

DeVorkin:

During these years of course there were some pretty provocative Hollow Square conferences, seminars, and summer session.

Aller:

Yes. The Hollow Square Institution of Shapley was a marvelous device. We would sit around actually a hollow square. Tea would be served with little lemon rinds. You would sip the tea — maybe Shapley’s version of the Japanese tea ceremony — and he would start the ball rolling. Everyone who was on the agenda had been forewarned, of course. After a few introductory remarks, he would call on say — George Dimitroff to describe some new gadget they had acquired for “the Ridge” (Agassiz station). Then he might call on Henrietta Swope or Dorrit Hoffleit to describe some curious variable star or statistics on meteors. There were special guests, who often were not astronomers,, but who brought in insights from other fields. One time our visitor was Professor Daly from Harvard geology department. Another time we had Professor Boring of the psychology department who talked about the moon illusion. There was a lot of free discussion in all of this, The great advantage of the Hollow Square was the relaxed atmosphere. You were more at ease than in a formal colloquia. There were formal colloquia, too; I recall some particularly stimulating ones by Henry Norris Russell. I had not been there for many weeks when I was called on to give a colloquium.

The topic was assigned by Menzel: to review a paper by d’Atkinson on a possible rotation mechanism for planetary nebulae, We were all convinced that these objects were expanding, not rotating. That idea had been discarded long ago. I felt rather queasy but it went’ off alright. One must credit d’Atkinson with an ingenious idea — even though it did not seem plausible. The Harvard summer school in astronomy was an outstanding institution. I attended two such summer sessions — in 1939 and 1940. After that they were suspended because of the war. The atmosphere was highly informal, but some of the lectures tended to be intensive. Some of the speakers would supplement their formal lectures with “tutorials” in which you met with the chap for discussions of troublesome points, etc. I’ve heard that the summer sessions of ‘35, ‘36, and ‘37 were great, but I cannot speak from other than hearsay about them. In 1939 we had a very nice summer session. Speakers included Findlay—Freundlich, who lectured on star clusters, and S. Rosseland who spoke on stellar structure. He was an inspiring teacher, whose writings did not do him justice. His papers and books were not easy to read. There were also individual lectures, e.g., Brian O’Brien spoke on flying experiments in balloons long before these sports became popular. In 1940 we did not have so many outsiders. Fortunately, Dirk Brouwer of Yale came and lectured on celestial mechanics presenting the subject in quite an attractive manner. Most of the lectures were given by local people who pitched in; Sterne and Schwarzschild gave a course on stellar structure. There were also lectures by Bok and other members of the Harvard staff. Alas, the events in the outside world — in May, June, July and August, 1940 were quite distressing and frightening and provided a distraction.

The last big astronomical event before the war closed in on us was the Yerkes meeting in September 1941 of the American Astronomical Society. It was followed by a conference on spectroscopy which had been organized by Struve. The whole affair lasted a week and was well attended. I had attended previous meetings of astronomical societies since the ASP meeting in Berkeley in 1937, where I’d given a brief paper. I became a member of the American Astronomical Society in 1938 and had attended meetings in New York (1938), Berkeley (1939), Columbus and Delaware Ohio (1939) and Philadelphia (1940) and had given papers at each of these meetings. At these meetings I felt with good cause that I was speaking as a student of Menzel’s. If the science was attacked, it was Menzel who could rise to the defense. The Yerkes ‘meeting was a different affair. Fred Whipple and Cecilia Payne—Gaposchkin had inspired me to undertake a spectroscopic study of Wolf Rayet stars with the slitless spectrograph at Lick. I had analyzed the data, measuring the line intensities and deriving what amounted to excitation temperatures. I was able to set limits on the densities of the radiating layers — estimates that appear to have stood the test of time and finally I drew some conclusions about the chemical compositions of these objects. The hydrogen content was negligible and there was no way of explaining all the spectra with a uniform chemical composition.[15] I wanted to get some slit spectrograms of these objects to supplement the slitless plates which were fine for deriving energy distributions etc. J. Allen Hynek invited me to come to Perkins Observatory where they had an excellent prism spectrograph. I was able to get a few plates, but the weather did not cooperate too well. A few days in advance of the meetings I arrived at Yerkes, where I met Swings for the first time and was able to talk to him and Struve about Wolf—Rayet stars and a few other object of mutual interest. They showed me their superbly beautiful spectrograms which obviously contained much of value beyond which they had already reported. I expressed my admiration and enthusiasm for their data I enjoyed the meetings and the spectroscopic conference and learned a great deal. I especially recall the paper by Wyse on his beautiful work on the spectra of gaseous nebulae.

It was the last time I ever saw him; his life was snuffed out nine months later in a dirigible accident in New Jersey. My own paper went off as well as I could expect; Robley Williams (then an astronomer at Michigan) warned me of some other dangers of spectrophotometer. A few weeks after my return to Harvard and just a short time before Pearl Harbor, Bart Bok called me into his office with most discouraging news. It seems that he or Menzel had written to Struve asking if he could find a job for me when. my appointment in the Society of Fellows at Harvard expired in the following year. Struve replied: “Aller showed up here; he would have walked off with every plate I’ve taken at McDonald and many of those at Yerkes if I’d have let him! He had two manuscripts he had written. Greenstein reported favorably on the one on Geminorum and Sirius. Swings was less impressed with the paper on Wolf—Rayet stars. He, Struve, had read neither but he was more inclined to accept the evaluation by Swings than that by Green— stein. I was flabbergasted and described to Bok exactly what had happened as well as I remembered it. I never knew the specific objections raised by Swings; I suspect they might have had to do with my conclusion that there were chemical composition differences between the two principal types of Wolf—Rayet stars. Pearl Harbor put the whole matter on the back burner.

I’m sure that neither Struve nor Swings were antagonistic towards me. It was just a matter of differences of opinion. Both of them were very friendly towards me in the years to come. Immediately after Pearl Harbor, I volunteered my services to the physics department to teach classes there. In the first part of 1942, I taught sections of the elementary physics course. Then, in the summer of 1942 I was appointed instructor in physics (salary — $2500/yr). Many of their own permanent physics staff had left for war work. I assisted Van Vleck in his undergraduate course in electricity and magnetism, by assisting in the laboratory and the quiz sections. I had my own course at the elementary level for the benefit of students who had taken the basic course for medics, biologists, etc. but now wanted to take serious courses in advanced physics. I stressed mechanics and elementary electricity and magnetism — such as you could do with a little calculus. I also had my own course in physical optics. This was a real challenge and a lot of fun. The class was extraordinary. One of the students was Roy J. Glauber, now a professor at Harvard; another was Jim Warwick. One day, one of the members of the class came up and asked if it would be possible to have a course in optical design and instrumentation. I told him point blank that I was ignorant of the subject. The man to ask was Jim Baker but he was doing other things. I said that although it would be much work on my part, I’d be glad to develop an optical instrumentation course, but I’d have to ask Professor Kemble, the department chairman. Now Kemble was a real gentleman, who was absolutely honest with his staff. He listened to my proposal and then replied: “Let’s think about his for a moment, I don’t think you would find it worth your while, First of all you would find it to be an enormous effort to develop the course. Secondly, since they teach optics in Rochester, we don’t need to bother here. Third, why go to all this work to develop a course you may give only once, because as soon as the war is over, all of you ‘hired help’ here will be dismissed.”

He was very frank and very honest, It was clear that there was no future for me at Harvard. I began to seriously question the wisdom of remaining. Menzel was already doing war work in Washington, the nature of which I do not know. He worked for the Navy. In early March 1943, Harold Weaver (whom I’d known in Berkeley) appeared for an interview for a fellowship. He suggested that I might get a job at what is now called the Lawrence Radiation Laboratory in Berkeley. He argued that since I had no future at Harvard according to my testimony I might as well be in Berkeley, where I might have a fighting chance for a job when the war was over, and that furthermore life would be better because of the more benign climate. Hence I wrote to Shane and he offered me a job. We left Cambridge at the end of May 1943. The Harvard years had been very good. Menzel had proven a wonderful friend and inspiring scientist to work with. He, Shapley, Bok, Whipple, Mrs. Gaposchkin, and visiting post—docs such as Spitzer and Schwarzschild, as well as students such as Jim Baker and Leo Goldberg had created an atmosphere of active research and inquiry into the most engaging problems in astronomy. But above all it was the friendliness and devotion to the welfare of us students that has made it such an excellent place. In that sense it resembled what I had encountered in Berkeley. To Menzel and Bok, particularly, I owe an immense debt of gratitude. THE BERKELEY WARTIME PERIOD

DeVorkin:

Let’s move on to the Radiation Laboratory (now called the Lawrence Radiation Laboratory) Berkeley What was it like there under wartime conditions? What did you do?

Aller:

A very large effort had to be devoted to separation of the 235 and 238 isotopes of uranium. As you know, several approaches were tried, including gaseous diffusion and electromagnetic separation by means of essentially a mass spectrograph. The Radiation Laboratory was devoted to the latter effort, Initially, I worked with an experimental group, on one of the so—called tank crews — filling liquid air traps for a vacuum system, plumbing, and even wrestling with a large brass plate (an activity in which my experience in the mining camp proved more useful than all that I’d learned in IJC or Harvard). I joined the staff in June 1943; then a friend of mine wangled me a job with the magnet group in September of that year. Dr. Powell, the head of the group, had been a cosmic ray physicist. Our task was to make sure that the magnetic fields in the tanks had good focusing properties. The experimental group had a device for measuring the magnetic field with flip coils. Then our particular group had the job of comparing the measured fields with theoretical requirements for good focusing. Our group went to Oak Ridge in September 1943 and stayed there until near the end of November when our task was completed. Then, we returned to Berkeley, My wife and son, Hugh, had to stay in Berkeley as there were no accommodations in Oak Ridge.

I was glad to return, Shane then asked me to evaluate the work of the chemists and the counting group who were analyzing the output of the electromagnetic separation process and assessing its efficiency. I responded: “But, Professor Shane, I really don’t know anything about chemistry.” “You are an astrophysicist, aren’t you?” “Yes, but what has that to do with an ignorance of chemistry.” “Therefore, you must be used to dealing with discordant data. Go and help the chemists straighten out their act.” The first step in the process was to extract the uranium and separate it from the contaminants, The uranium, in the form of a compound that could be deposited as a thin film, was placed as such on a thin disk and weighed. It was an interesting exercise in quantitative analysis, which I appreciated because I’d not had an opportunity to take a chemistry course while I was a student at Berkeley. The $3 lab fee in physics was reasonable and manageable, but the $28 lab fee in chemistry placed it just beyond the limit of my resources. I worked through the analyses and found that the chemists were doing OK. The problem had to lie in the next step. The overall efficiency of the process as a separation scheme was measured by the increase in the U(235)/U(238) ratio, a quantity that had to be established by fission counts. Slow neutrons produce fission in TJ(235) but not in U(238), so the technique consisted in producing slow neutrons in an appropriate source and allowing these to impinge on the sample. At the same time, counts were registered from a standard in which the 235/238 ratio was supposedly known, Natural uranium contains so little U(235) that with the existing equipment we had problems with the statistics. The man in charge of the counting group was David Fox. (In those days I used to ride with Wolfe to work with Fox).

He seemed to be a capable fellow, The discordances were very puzzling and of such a nature that I concluded that there was something wrong with the standards and we should get new ones, but how would you know the true 235/238 ratio? Starting out from the beginning, working in isolation, we felt that the only sure way was to use natural uranium as a standard. This meant upgrading the apparatus, and while 1 gram of radium had sufficed as a source in the first model, we felt that it was necessary to now use 10 grams of this expensive, lethal metal. Fox designed and built the “Bathysphere” a massive structure with thick lead walls that would prevent alpha particles from escaping and with which we felt we could now use natural uranium as a source. As I recall, it took over a year to complete this monstrosity and it was not until the spring of 1945 that the device was ready for testing. About that time, a physicist from Columbia arrived to discuss counting techniques, etc. We explained our troubles, in particular, complaining about 10% errors we were struggling with, He asked if we had seen his report, a copy of which had been sent some time previously to the radiation lab. “Read your report,” we replied, “we did not even, know you existed.”

The security people were so fearful that we might learn that somebody else was working on these things, that access to this information was blocked. Now we were able to find out what progress had been made on these problems. We learned that accurate standards were available and the lead bathysphere was obsolete before it had been really completed, New and more efficient counting circuits could be built. Fox immediately went to work to build a new counting system, which together with new, accurate standards would increase accuracy to a fraction of a percent. We knew that several labs were involved in the process but we did not know their identities, so we proposed that the standards be prepared in some appropriate laboratory and made available to laboratories. Test samples would also be pre— pared. Then the standards and test samples would be distributed to the laboratories through one agency, so it was never necessary for anyone except those in the central agency, to know the identities of each of the labs, The security people were delighted with this arrangement. Thus, in April 1945 we felt that with new equipment being designed and built the assay problem could be solved in a satisfactory way. Early in 1944, Professor H.S.W. Massey became head of the theoretical group in which I was working most of the time. We began to look into the basic physical processes governing the ionization of atoms in the electric arcs which were the source of ionization for the mass spectrograph separation system. We even had our own experimental division that worked with gases that were more amenable to theoretical studies, rather than with uranium compounds which could not be so easily handled. We looked at such things as the influence of arc configurations on ionization efficiency, and tried to collate experimental findings with theoretical considerations.

Massey was a wonderful fellow to work with. His outstanding capability in theoretical work and his excellent feeling for experiments inspired all of us on his team. Also, on “time off” I could talk to him about atomic collision processes which are so important in astrophysics, quantum mechanical calculation techniques, negative ions etc. We looked into the possibility that other negative ions, particularly those of oxygen and the halogens might contribute appreciably to the solar continuous absorption coefficient and concluded these ions were probably not important. We even wrote a paper on the subject but did not publish it because Massey felt that Nazi spies might deduce that he was in the USA. In spite of heavy demands of the war work, I tried to maintain some activity in off hours on pure science. Fortunately, I was able to arrange with C.D. Shane to take my time off in blocks of 3 days every 3 weeks instead of 1 day a week, so that I could to up to Lick to observe. I spent my vacation time at Lick, all told making some 19 trips up there in the course of 2 years to observe mostly with the Crossley. The main thrust of the program was to extend the planetary observations that I had made for my thesis to additional objects, especially those that had been observed by A.B. Wyse in his classic work on the spectra of 10 gaseous nebulae (Ap.J. May 1942). I used the Crossley slitless spectrograph, covering the spectral region from the green nebular lines to 3000A. It was possible to measure only the strongest lines. I measured many of the plates with the Moll microphotometer at Lick and reduced them in Berkeley, but most of the measurement and analysis had to wait until after the war. The program included a number of objects of low surface brightness and of low to intermediate excitation.[16] Neubauer had called my attention to a remarkable Wolf—Rayet star with narrow emission lines and an underlying A—type spectrum, HO 45166. I applied to it the same type of analysis as I’d used on my previous analysis of WR stars and we concluded that the composition was not the same as that of classical Wolf—Rayet stars.[17] Sarah Heap of NASA and I have again examined this object and find it to a very interesting system. Massey’s group included a very capable young theoretical physicist, David Bohm, who now has a position in London, The Japanese astrophysicist, Hagihara, who has also done some splendid work in celestial mechanics had suggested that the velocity distribution of electrons in the ionized gas of a planetary nebula or in the interstellar medium might depart appreciably from the Maxwellian. The series of papers on physical processes in gaseous nebulae by Menzel et al. was based on the postulate that the velocity distribution of the electrons was Maxwellian.

I felt that Hagihara’s suggestion was not justified. I talked over the problem with Dave Bohm and got him interested in working with me on it. Quite simply the problem can be envisaged in terms of comparing the rates of processes that tend to destroy a Maxwellian distribution (vz. photoionization, recombination, collisional excitation of levels, free—free emission) with those that tend to restore a Maxwellian distribution i.e., Coulombic interactions with electrons and between electrons and ions. It turns out that the energy exchange in Coulombic encounters dominates to a high order of magnitude and consequently the gas adheres closely to a Maxwellian distribution,[18] We used to work on this problem at my house in the evenings after the days chores were done at the laboratory. Also, I reassessed the calculations in my thesis and (under Massey’s suggestions) attempted to estimate collision rates for other ions, I attempted to determine the chemical compositions of a number of planetaries, using both Wyse’s observations and my own, and the best physical theory of recombination rates etc. available. The final paper by Menzel and me ended the series on physical processes in gaseous nebulae.[19] One scientific project on which I spent much time during the wartime Berkeley years was the theoretical calculation of the intensity ratio of the “resonance” forbidden transitions of (011). , 3729/3726 in the ground 3p3 configuration. I had noticed that the ratio predicted by Pasternack did not agree with the observed ratio. In fact, the transition that was predicted to be the stronger was invariably the weaker. While I was at Harvard, I discussed this with Wilbur Ufford, who was on leave from his regular post, teaching physics. We thought it might be due to configuration interaction, but Van Vleck pointed out that this was extremely unlikely and that we should examine the second—order spin—orbit interaction and the spin of one electron interacting with the orbit of another. These effects turned out to be the significant ones, but the calculations were very involved with frequent opportunities for errors in sign. We started the calculations at Harvard and pursued them vigorously as time would permit 1943—45. In August 1945, at McDonald Observatory I was able to obtain adequate data for the 3729/2726 ratio in a number of planetaries. The ratio depended on the density of the nebula, approaching the theoretical value under conditions of high density. We realized that this (011) ratio would be a valuable discriminant of electron density in gaseous nebulae.[20] In addition to working on science in the evenings and Sundays as opportunities permitted, I felt that it was desirable to discuss progress in astronomy with other astronomers in the community. Many, like myself, were temporarily there engaged in war work, Harold Weaver and I worked out a program for the first of these journal club meetings which was held in my home on Mann Avenue in Berkeley. We invited all the astronomers we knew, The first meeting was well attended. Among those participating were Popper, Robert Aitken, and Franklin Wright (inventor of the Wright—type camera). We discussed possible planet—like companions of binaries, a topic on which we could get the opinion of one of the best double star observers of the world, and also a number of other items —— some of them devoted to what we could expect in the way of new technology after the war. Crawford boycotted the meeting, taking the point of view that such discussions should be held at the observatory. Thus we attempted to hold the second meeting at the observatory as Crawford requested. It was a failure. Only Crawford, Weaver, one or two others, and I showed up. We just adjourned and went home, I never attempted to continue the effort. Under the inspired leadership of Professor H.S.W. Massey things seemed to be going well. Then, suddenly, in early May of 1945, when it became evident that the fall of Germany was imminent, rumors began to circulate in the laboratory that there was going to be a purge of the staff,

DeVorkin:

For what reason?

Aller:

Director E.O. Lawrence decided to cut back, When I showed up for work on Monday morning, May 14, 1945, I was told to report to the office of Ralph Chaney. Professor Chaney, a paleontologist, was assistant director of the lab. I had been in to see him a week before when I’d first heard these rumors, At that time he told me I could stay on until Fall when I could go to a post—war job in Indiana, Now he tersely informed me that “my services were no longer required.” That is, I was purged. I’m sure that Professor Chaney has been acting on good faith. A retrenchment in the size of the laboratory staff was understandable, perhaps, What has never been understandable to me was the manner in which it was done, Faced with the necessity of a cutback, one might have supposed that the director of such an enterprise would have called in the chiefs of his various divisions, explained the situation to them, and asked them to decide who ought to be kept and who ought to be let go. That was not the way it was done. Professor Massey walked into his office one day to find a list of names with the notation to the effect that these people were to be dismissed — no argument — no discussion, it was just thus and so, We could find no pattern for those who were kept and those who were purged, Probably about half the staff of the lab was sacked.

This callous, calculation action made a profound impression on me that time has not tarnished nor the years mellowed, To put it concisely, the abiding reward for conscientious service was a swift kick in the face, The purge in the lab taught me a lesson, It drove home the utter contempt with which the militarists and their ilk hold scientists, I never forgot, NEVER! The effect on some of my associates was devastating, Fox was right in the middle of the development of his new counting system, but he needed more time than the 30 days we were all given, He went up to talk to Director Lawrence, pleading for six weeks instead of 30 days to complete the counting system in which he took pride and to which he had devoted much effort. Lawrence is reputed to have said: “Well, I’m no longer interested in this problem. You are purged and that is it” — or words to that effect. Thus, Fox also was purged. Poor Fox was among those mentioned adversely in the notorious Oppenheimer security hearing. I’d heard rumors that he was regarded as politically unreliable while I was at the lab, but I would not say he was purged for that reason. I do not think that I was purged because I might be suspected of having politically unpopular beliefs. I think all of us were purged as a matter of expediency.

DeVorkin:

What date was this, again?

Aller:

May 14, 1945.

DeVorkin:

I see. So the bomb hadn’t been dropped.

Aller:

No, it had not been even tested, let alone dropped.

DeVorkin:

Did you know about the bomb at that time?

Aller:

I knew they were building one and that there had been a race with the Germans. When we started to work on the project, we all believed that they were making one and we had to get there first, so they would either be checkmated or bombed first. As it became evident that Germany was collapsing and the war would end there without use of the bomb, many of us saw no reason to use it on the Japanese. They did not have it and were not building one. With such a fiendish weapon as this, one should warn the intended victim and give him a chance to sign on the dotted line before you blasted him to Kingdom Come. Bohm was among those who argued against using the bomb, on what I considered very humanitarian grounds. Actually, I got in on but little of these discussions because I’d been purged long before the bomb was even tested, There was a conversation I had with one of the bureaucrats in which he so well summarized the attitude. of the top brass to the humble scientists who were trying to do their bit, that I must review it here. After I’d been given my thirty days notice, I decided to stay on the job and collect my pay until the last allowable hour. Most of my fellow purgees had left, scurrying to get other jobs before their draft boards got a job for them.

As noted later, I’d already arranged to go to Indiana, but my duties there were not to start until September. On one of my very last days I got on the bus to go to the main lab on the top of the hill to close out some work I’d been doing and file a final report. There were very few people around compared to the numbers who had worked there earlier. As this bureaucrat got on the bus he remarked that things were pretty quiet now that they had gotten rid of all the riff—raff and third—raters. To all of this I replied that many people who had been working on the project took a certain amount of pride in their work, that they enjoyed doing tough technical jobs well, and seeing them successfully completed. Consequently, they felt very badly about having been deprived of an opportunity to finish what they were working on. The bureaucrat asked “And why are these people deserving of any special consideration as compared with, for example, shipyard workers.” I replied “Scientific work is a little different from working in a shipyard. You have long term projects, ideas, or experiments in which you are engaged and which you are eager to see completed. It is something novel or challenging, something you early desire to see through. Working in a shipyard is quite a different task — routine production work instead of challenging research and development work, Finally, when you kick these people out, maybe they will not come back when you need them.” The bureaucrat, who obviously never dreamed he was talking to a purgee, gave a lovely answer: “Oh, they are so dumb, they will come back — like a cur dog to his master’s whistle,” There was one cur dog who had more sense, The work at the Radiation Laboratory had been a valuable experience in many ways. L worked with a number of outstanding and capable scientists, among whom were Terrell Hill, David Bohm, H.S.W. Massey, Eric Burhop, Richard Dempster, and I met many more. But in the end there was the terrible frustration of not being able to complete the job on which I had been working — to see the assignment through to its final solution. I felt that many of my hardest and most conscientious efforts had been in vain. My last working day at the Radiation Laboratory was June 13, 1945. Fortunately, by then I’d arranged to get a job in Indiana, and actually had been appointed to the job (although as yet without pay). I planned to work a month at Mt. Wilson and then proceed to Texas where I was to meet my new boss, Frank Edmondson, We had to sell our house, pack up, and move east — troubles and anguish.

DeVorkin:

How did you get the job at Indiana?

Aller:

It was through the recommendations of Frank Edmondson, I believe. He, also, was a graduate of Harvard but finished before my time. I met him at meetings of the American Astronomical Society. The inquiry about a job came not from Edmondson, but from Dean Fernandus Payne, One day early in May, 1944, I came home from work to find a letter from him, announcing that Cogshall was retiring and they wanted to replace him; my name had been suggested. At that time the end of the war seemed far away and I replied that I was very uncertain about when I might be available. I discussed the feeler with the people at Lick, especially Doc Moore, who had so generously arranged for me to come up there to observe with the Crossley. He expressed surprise that they were willing to commit themselves so far in advance; the Lick people were not going to make any appointments until after the war, I also wrote to Shapley and to Bok who gave me very good advice, Shapley (in particular) pointed out some of the advantages of Indiana. I deduced from his letter that he may have recommended me to Dean Payne, as perhaps did Edmondson. The intensification of the war in the Summer and Fall of 1944, and the failure of Germany to collapse in late 1944 slowed down discussions until early 1945. My initial impression was that research opportunities at Indiana would be very limited. They had a venerable 12—inch refractor, excellent for teaching purposes, and some photographic equipment.

However, they had access to the new Goethe Link Observatory with its 91 cm reflector and Edmondson described how they bought time on the McDonald Telescope in Texas, all of which would upgrade the research opportunities to something considerably better than I had anticipated. Obviously, it would have been better (research—wise) to have a position at UC, but they had never indicated that they were even considering me, Likewise, there might possibly be openings at other observatories that did have spectroscopic equipment. Hence, before I had proceeded very far with the Hoosiers, I wrote to my old mentor, C. D. Shane, who was destined to become director of Lick Observatory. I described my dilemma and the fear of not being able to have access to adequate research opportunities. If Shane’s letter had been datelined, Delphi, I would not have been surprised after I read it, He said that although teaching jobs had to be filled to meet specific schedules and obligations, research positions in an observatory could be filled in a more leisurely way, Any appointee from a teaching job would be allowed to finish his term or year. The very specific advice from this future director of Lick Observatory was interesting, confusing and in the end quite wisely rejected. He wrote: “I think it would be a mistake to accept an appointment at Indiana for more than one year.” Starting in early 1945, I began negotiations in earnest with the Indiana people. Edmondson described to me in detail the research arrangements with the University of Chicago and McDonald Observatory and wrote enthusiastically of their plans for the Lick Observatory.

Everything was worked out to our mutual satisfaction and in the spring of 1945 and before the purge in the laboratory, I had accepted a position at Indiana, for 3 years with strong possibility of a continuation, Negotiations were done just in time, Of course, when we were purged at the Radiation Laboratory, our draft deferments were immediately cancelled, so unless we found another job, forthwith, we would be called up. On Monday evening, after Chaney told me I had been sacked, I called up Edmondson, explained the situation to him and as he remarked later, “the wheels turned very fast,” I was immediately appointed a staff member (without salary until I came to Indiana and started to work), A draft deferment was requested for me and was granted by my draft board in Crescent City, California, This meant that if I could henceforth do astronomy as I wished and not just in my spare time, but I would not get a paycheck until I went to work for the Hoosiers. There was, of course, no such thing as termination pay for purgees. Fortunately, I was able to spend a month (July 20—August 20, 1945) at Mt. Wilson Observatory. Minkowski took me up to the observatory where we observed the near infrared spectrum of NFC 7027 with a fast spectrograph of a IN emulsion.[21] We found a number of interesting spectral lines in this region and realized that similar observations could be secured for other planetaries. Merrill had taken a number of widened spectrograms of Am and Ap stars and suggested that I might like to work them up. The plates were of excellent quality but of tantalizingly low dispersion. I tried to extract such abundance information as I could from them by curve of growth methods but it became clear that higher dispersions would have to be employed.[22] I found some plates of 10 Lacertae in the files, including a number of excellent coude spectrograms. I measured these and analyzed them for abundances by Unsold’s method.[23] The results were encouraging and suggested that it would be worthwhile to examine the spectra of additional early type stars, a project I undertook the following year. Then, I proceeded to McDonald Observatory to meet Frank Edmondson who showed me how to use the 82—inch reflector and spectrographic equipment.

Here I worked mostly on the spectra of the central stars of planetary nebulae, especially those showing absorption line spectra. From analyses of the line profiles and intensities I hoped to compare their atmospheres with those of population type 10 stars and derive effective temperatures and perhaps estimate surface gravities as well.[24] This survey picked up an interesting example of an OVI star, the nucleus of NGC 246. The Hoosiers were as good as their word; they did everything in their power and resources to provide research opportunities. Unfortunately, living conditions were unsatisfactory. I arrived to find that no accommodations were available. We got a place in the country, about a miles walk from the end of the bus line. We stayed there 1945—46 winter but were evicted at the end of April and had to live in a hotel. The next two years Hugh and I boarded with a family while Rosalind completed her work in medical school. Let me describe them simply as interesting characters, whose attempts to break up the family, sleazy treachery, and cunning malevolence are resurrected in nightmares even to this day. At Indiana I wrote the first draft of my two astrophysics volumes which were later published by Ronald Press Co.[25] I prepared the rough text, duplicated it, and circulated it to members of the astronomical community. The project was actually undertaken as a consequence of encouragement by Henry Norris Russell. Otto Struve read the text with care and sent me pages of detailed suggestions. Helpful comments were made by many other astronomers. A difficulty with the Indiana situation was that there one was dependent on outside institutions to carry on your research. I used the McDonald telescope again in 1946 and travelled to Yerkes to use their microphotometer as none was available at Indiana, Here I was able to trace the plates I had secured at McDonald and those I had brought from Lick.

For the first year and a half all went well, Then, in the spring of 1947 — just after Kuiper had replaced Struve as director of Yerkes, Edmondson and I travelled there to attend a “neighborhood t’ meeting of Midwest astronomers. Kuiper called me alone into his office for “a little chat.” I naively supposed that, as new director, he wanted to know what research problem I was working on there. It soon became obvious that he was not interested in knowing about anything I was doing. He quickly got to the point: there was not much of a future in the arrangement whereby Indiana bought time at McDonald Observatory. If I wanted to work as a stooge for some member of the Yerkes staff, that might be possible, but there were to be no independent programs of my own. He wanted all the McDonald observing time for himself and his own people. When I told Edmondson about this afterwards, he was surprised, as he had heard nothing of that kind from Struve to whom he had been talking while I had seen Kuiper. A very short time after we returned to Bloomington, I got a letter from Struve to the effect that if I would quit Indiana and go to work for the University of Chicago — “teaching the more elementary aspects of our science than those involved in my astrophysics notes,” I would be guaranteed time at McDonald Observatory during the summer quarter. Shortly thereafter I got an invitation to come to Chicago for an interview. I left Indiana on a lovely spring day and arrived the following morning at the 65th St. station in South Chicago, where I got off and walked to the campus. The proposed teaching load was horrendous. They wanted me to teach some proper elementary courses in astronomy, but the largest burden would be in their courses based on the so—called Great Books. To put it concisely, it was a philosophy of science teaching with which I am in fundamental disagreement. You do not waste the time of students asking them to read translations of the Almagest, De Revolutionibus, or Kepler’s Music of the Spheres when they can read George Abell’s Exploration of the Universe, or its nearest equivalent as existed at that time.

I spoke to them quite honestly about my views, but to my surprise they offered me a job as an assistant professor on the Chicago campus. At almost the same time, I got a feeler from Leo Goldberg at Michigan, telling me that he was hoping to get me an appointment to a tenured position there in 1948. His letter was a friendly, informal one. As director, he had been promised a position for a colleague and he would like to have me join him there. So, if I left Indiana, I could choose between a temporary job at Chicago or a tenured position at Michigan. I promptly wrote the Chicago people that I was not interested in a non—tenured position there. I spent most of the summer of 1947 at Harvard, where I gave a few lectures and tried to do some research. Then I went to the astronomical meeting which was held at Northwestern University and returned to Indiana to teach in the autumn. The anticipated offer from Michigan came early in 1948; it was a very good one with provision for time to travel to other observatories to secure observational data. I would have accepted it at once except for a curious situation that had developed in the interim. Menzel had informed me that Shapley was trying to secure for me a position at Harvard and would I please stall Goldberg off until they could see what, if any, offer they could contrive, Leo knew about this and agreed reluctantly to allow me a month in which to decide between his offer and any offer that Harvard would make.

The day before the deadline, Menzel called me to inform me that there would be no offer from Harvard, so I accepted the Michigan one. Some clues to what really happened may be deduced from the following anecdote: Just before I accepted the Michigan offer, their Dean Keniston (who was a good friend of the astronomy department) met the then president of Harvard and mentioned to him that both Michigan and Harvard (so he had been told by Shapley) were trying to hire me. “Oh, replied the Harvard chief,” “Did Shapley tell you that? That’s what he thinks!” At that particular epoch, Shapley was in trouble with the top brass of Harvard because of unpopular political views. Some of them felt he should be punished. To deny an appointment requested by the observatory was an obvious move. My own qualifications (or lack of them) were irrelevant. There were several reasons for leaving Indiana, First of all I was very unhappy with living conditions we had encountered in Bloomington, but in retrospect it is possible that they would have been comparably bad elsewhere. I don’t know. Second, and more important, my colleagues, Edmondson and Cuffey worked in quite different fields from my own. There was no astrophysicist or stellar spectroscopist with whom I could talk, unless I went to another observatory or university. On the other hand, at Michigan, there were a number of people with interests and background much closer to my own. Besides Leo Goldberg, who also had been a student of Menzel’s, there were A. K. Pierce, Helen Dodson, and Orren Mohler in the solar research field, and the stellar spectroscopist, Dean B. McLaughlin. Furthermore, Leo was planning to employ additional creative staff members. Third, there was the question of instrumentation, Indiana had a 91 cm telescope, but no auxiliary equipment. Michigan had a 95 cm telescope with spectrographic equipment which was not quite so obsolete in 1948 as it was soon to become.

There was the splendid solar observatory at Lake Angelus and a 61 cm Schmidt telescope was being constructed. Indiana did have the advantage of being able to buy time at McDonald, but the little chat with Kuiper had me very much worried. If I did not have access to spectrographic equipment, I was out of business, I felt that Michigan was entering a period of great creativity. I would like to emphasize that the Hoosiers tried to do what they could to make my stay in Indiana pleasant and productive. They really wanted me to stay and asked if there was anything they could do for me. At the time I did not think they could meet the Michigan offer in terms of opportunities for research, Their friendliness and generosity stood in stark contrast to what I was destined to encounter in Michigan a dozen years later. The Hoosiers made it possible for Rosalind to complete her medical degree at Indiana University Medical Center in Indianapolis. The Indiana years were not easy ones, but I believe they were three of the most productive years I’ve ever spent. Frank Edmondson was sympathetic to my research and teaching endeavors and lent a helping hand to secure support when I needed it, He built up a good department in Bloomington and he created many jobs for astronomers, both there and through his efforts in the National Science Foundation. Astronomy needs people like that. I enjoyed working in Frank’s department.

By the late forties, Michigan had become a very active research center. Goldberg had ambitious but realistic programs for building up a graduate department that would be at the forefront of astronomy. At Lake Angelus the most exciting development was the application of the lead sulfide cell (which had been developed at Northwestern University) to an exploration of the infrared solar spectrum. With this device they were able to make the first modern atlas of the infrared region. Goldberg, Mohler, and McMath were actively engaged in this endeavor and exploiting the advantage, thereof. Helen Dodson was observing solar prominences and flares. Keith Pierce was measuring the limb darkening in the infrared solar spectrum; one of the first projects I undertook in Michigan was to work with him in an attempt to deduce the solar atmosphere structure from these data.[26] In Ann Arbor, Freeman Miller was working on galactic structure and making plans for the new Schmidt telescope that was promised for delivery in the summer of 1950. Dean B. McLaughlin was continuing his work on B emission stars and novae. Hazel Losh taught the large elementary courses, She remembered every one of her students, their names, faces and interests. Her classes were packed; her huge enrollments provided magnificent statistics for the astronomy department at the dean’s office and made it possible for the rest of us to carry out our own research programs and teach relatively small classes. The youngest member of the teaching staff was Carl Bauer who had done a thesis on W Serpentis (a star that has turned out to be so interesting with the ITJE).

He not only switched fields but moved from astronomy to one of the most difficult areas in chemistry, measurement of trace amounts of gases. in meteorites. He got support from his endeavor from the Office of Naval Research, but before he got the experiment working adequately his term of appointment ran out. Since he was not recommended for promotion to a tenured position, he was dismissed, In the early fifties, Stan Wyatt was appointed to fill the position vacated by Bauer. In the late fifties, Wyatt went to Illinois; Bill Liller then accepted the position. It was clear, however, that although Leo Goldberg was director, the influence of Robert McMath, l’eminence gris, was pretty important. He, his father and Judge Hulbert had founded the observatory. The elder McMath was long since gone when I arrived in Michigan, and Judge Hulbert had been incapacitated by a stroke, The solar observatory had been greatly expanded since it was first founded. Robert McMath must be given due credit for the substantial progress that had been made, Their original work had been photography of solar prominences, but they had developed much more advanced and versatile research programs. McMath, who had been trained as an engineer, was a very successful business man. It was evident that he believed that some of the methods of big business could profitably be applied to science: the man at the top makes the decisions and the employees do as they are told. He used to come out to Lake Angelus one day a week, where he would discuss with Goldberg, Mohler, Pierce and other members of the staff current research and new plans.

McMath set high standards for himself and for those who worked with him, One had to be very careful not to offend him by some unintentioned oversight or action he would interpret as a slight, Goldberg briefed me on the proper court etiquette to be followed in his presence, but even this was not always adequate. Soon after I arrived in Michigan, Goldberg had entrusted me with a responsible role in developing a graduate program. I suggested that the obvious thing to do was to bring the students in close contact with the research going on at Lake Angelus at the McMath Hulbert Observatory. Staff members could lecture to students on their research fields; my hope was that they could even be enticed into working on research projects on a cooperative basis. Leo gave me the impression that he would talk it over with McMath, forthwith, and explore what could be done, Sometime later, Sir Harold Spencer—Jones visited the university. At the banquet given in his honor, I was seated near McMath and Goldberg. I happened to bring up the subject of this proposed program for students, on the assumption that Leo had discussed it with McMath. Apparently, under the pressure of other matters, he had not. McMath exploded in a tirade against me - as though I were trying to run his observatory behind his back. I expected Leo to try to smooth things over, but I’ve never seen him so completely silent, Finally, McMath ended the tirade with the words: “We’ll carry on; we’ll carry on!” I dropped the whole proposal and never mentioned it again. A prominent astronomer of the older generation once remarked to me that McMath was the most conceited fellow he had ever met. I replied that this was a remarkable statement from a man who had known T.J.J. See, to which the old fellow replied; “McMath was successful!”

My years in Michigan were productive, Leo tried to get excellent people there and developed good research projects. He arranged that I had plenty of time to do research and had time to go to Mt. Wilson and Dominion Astrophysical Observatory. Such data—gathering visits were absolutely essential. I am basically a stellar or nebular spectroscopist. Thanks to the Mt. Wilson guest investigator plan, which had been initiated by Bowen, I was able to carry out a number of programs, e.g., high dispersion coude stellar spectra, slit/spectra of bright planetary nebulae (with Minkowski), and slitless spectra of compact bright planetary nebulae. In 1954 and 56 Liller and I obtained a number of photoelectric measurements of planetary nebulae. In those days, the Mt. Wilson Observatory played the role of a defacto national observatory. They allotted time generously and evaluated proposed programs very reasonably. Perhaps the essential contribution to what success I’ve enjoyed in astronomy was the opportunity offered by Mt. Wilson Observatory. I was able to get excellent data to take back to analyze myself or to work on with my students,

DeVorkin:

Was this with the 100—inch primarily?

Aller:

We obtained data with both the 60—inch and 100—inch. By having access to this telescope and accessory equipment, I had excellent opportunities throughout the fifties there for research. I’ll try and give some specific details later. There were some basic limitations: (a) you could not bring students with you, and (b) there was no guarantee that time would continue to be available. The restriction on student participation was not too serious since we did not have funds for such a purpose, Once in a while it would have been nice to take an advanced student with you, but the rules were quite explicit and strict. The second factor was far more important, and in the end decisive. The number of applicants was increasing and the Mt. Wilson—Caltech people needed more time for their own programs and students. The amount of time available for your program would eventually become very restricted. Except for solar observations, the opportunities at Michigan were very limited, We had a pre—World War I, home—made, 37—inch telescope.

There was also a Schmidt camera equipped with a pair of objective prisms which was located in a forest preserve at a place called Peach Mountain which was neither a mountain nor were there any peaches growing there. Sometimes they called it Portage Lake which was a complete misnomer as it was not on the lake; it was about 40 minutes drive from campus. The telescope was useful for survey jobs, spectral classification etc. requiring nothing more than low dispersion spectra or direct photographs. It was useless for anyone interested in detailed spectroscopic information on stars or nebulae, The telescope has been moved since to Chile where excellent observations have been secured with it for the revision of the Henry Draper Catalog. As far as spectroscopic problems of interest to me were concerned, the Michigan equipment was obsolete and quite uncompetitive. Goldberg and McMath on the one hand, and several members of the staff, including me, on the other — had a fundamental difference of opinion about instrumentation. We wanted a telescope that would be a Michigan instrument, that was modern, up—to—date and competitive. Goldberg’s argument was why bother to have a telescope of your own when you can go out and use the equipment at Mt. Wilson. This is fine as long as your host institution has plenty of time to allocate to visitors, but it became apparent to me before the end of the fifties that Mt. Wilson would not be able to take care of all the needs of visitors, much as they might like to.

Towards the end of the fifties, Goldberg argued that Kitt Peak would take care of all our needs, In the end, it became obvious to me that if I wanted to continue with viable nebular or stellar spectroscopic work, I would have to be at an institution that did have some equipment of its own, Goldberg was head of the Michigan department during the twelve years I was at Michigan, not chairman of the department in the sense of a UC department chairman, but head man! In other words, in collaboration with his grey eminence, Leo made the decisions. Goldberg talked to the administration, but the deans and administrators never talked to anybody in the department except him. The administrators accepted his opinions and representations as the considered opinion of the department. During all the time I was at Michigan, nobody ever asked my views on anything until Goldberg quit in 1960.

DeVorkin:

Why did he quit?

Aller:

Essentially because he got a raw deal from the administration.

DeVorkin:

After all this?

Aller:

Yes, after all he had done to build up the department. It is a long story and I know only the broad outlines, In 1948, when I arrived, there appeared to be much sympathy for astronomy at the University of Michigan. Dean Keniston was very enthusiastic and the president of the university was a good friend of McMath, but by the end of the fifties, things had changed, for the worse. There was an argument over priorities for a new building. Both physics and astronomy were crowded in their respective structures and wanted a new building which they could share. This was at the time of Sputnik when there was a great upsurge in interest in physical science, and demand for room in which to work. The president of the University of Michigan was Harlan H. Hatcher who had previously been vice—president of the Ohio State University. I never met this gentlemen. He always seemed to be elsewhere, lecturing the people of Samarkand or Bogota on the purpose of a university. He was a great enthusiast for the Little Theater, His deputy was Marvin Niehuss, with whom in 1960 I was to have a most interesting and decisive interview, I consider this pair to be the least competent administrators I’ve ever met in a top posit.ion in my life, They told the legislators in Lansing in 1958—59 that what the university needed most of all was not a new physics building, but a new music building.

The legislators cynically answered “You cannot beat the Russians by tooting a horn, If you assert that a new music building is more important than a physics building, you are talking nonsense and you will get neither,” Goldberg and the physicists tried to get them to reconsider their priorities but they continued to drag their feet on the matter of a physics—astronomy building. Goldberg wanted to develop space astronomy projects, in particular devices to look at the sun in the ultraviolet and studying its UV and X—ray spectra in more detail. He desperately needed the space for these projects. It is obvious to anyone of ordinary intelligence that such projects would have been of great value to Michigan. Leo’s friends at Harvard had been watching with great interest what was going on. They offered him a fine deal and also a tenured position to Bill Liller who was then an assistant professor at Michigan. Both of them accepted the offers, Then, after the horse was stolen, they locked the door, The new physics—astronomy building was approved! The administration was quite upset, because to them, Goldberg was the astronomy department. Vice—president Niehuss who had once asked McMath “What has astronomy done for the state of Michigan” announced that the department had been “gutted.” Aside from the fact that they had brought this situation on themselves by their own ineptitude, and therefore had only themselves to blame, they thought that Goldberg was the only scientist who amounted to anything in the department. All the rest of us were clunkers.

A few weeks after Goldberg had announced his decision to leave, I went to talk to Roger Heyns, then dean of the college of arts, literature, and science. He later became chancellor at Berkeley. He listened to what I had to say, but he had no power, and all he was able to do was to arrange for Fred Haddock and me to talk to Marvin Niehuss. I hoped that I could explain to him that we had an obsolete telescope which would have to be replaced by a modern one, hopefully in a better location. I naively anticipated that his reply would be: “All right, but we don’t have any money for it,” but that he would view such a situation with sympathy. Briefly, I told him how we had been working with a pre World—War I home—made telescope, and that we could not compete in the sixties with a 1912 telescope. His reply was very interesting: “What are you fellows yelling about? You’ve got a new building, haven’t you?” He was not in the least bit interested to learn that there had been other ideas and priorities than those pushed by Goldberg, Obviously, we were regarded as inconsequential peasants. Niehuss ended the interview with a remark that made me decide then and there to leave Michigan, as soon as a suitable, alternative choice could be made, viz, “If you all leave, we will replace you.”

DeVorkin:

That was the same attitude as the fellow at Lawrence Radiation Laboratory.

Aller:

No, the Radiation Lab boss was much worse; his attitude was in essence “I don’t give a damn what you are doing. You’re purged.” Niehuss’s attitude was: “we don’t give a big big D if you leave,” By inference if you hang around don’t expect to get any help from us, This implication, not explicitly stated, was clearly enough given and was decisive. The decision was taken reluctantly; at Michigan I’d had a number of excellent students and had been able to carry out some long research endeavors. I had some excellent people to work with,

DeVorkin:

Who particularly stands out?

Aller:

Perhaps all of them, but for different reasons. My very first PhD was Shu Mu Kung, who had gotten his MA in Berkeley. Goldberg announced to me one day that Kung was my student. He was a very interesting fellow, whose outspoken political views got him into trouble. I believe that he returned to mainland China and had a successful career. Bill Liller, who is now at Harvard, did a thesis on photoelectric photometry of planetary nebulae. Albert Boggess, who is in charge of the IUE program at NASA, did a thesis on narrow band pass photography of diffuse nebulae and H11 regions. Theodore Stecher, who did not actually get a degree with us, has carried out an outstanding research program at NASA. Jun Jugaku, who is now at Tokyo Astronomical Observatory, worked on the interpretation of atmospheres of B stars. Joe Chamberlain, now at Rice University, interpreted the spectrum of the Network Nebula in Cygnus and collisional excitation of excited atomic levels. There were the Canadian students; John Climenhaga (a dean at a University in Victoria B.C.) worked on the carbon isotope ratio while Jean McDonald worked on atmospheres of B stars.

These and other students worked with me on a variety of topics, some of them rather different from the subjects they chose for their theses. I’d like to describe some of the work that I did while at Michigan, because these were very productive years. Some of the projects involved equipment at Michigan, some involved data secured on Mt. Wilson (and occasionally elsewhere) and some were theoretical. Some programs involved the 37—inch. One was a study of the combination or symbiotic variables, CI Cygni, BE Cygni, and Z and which was carried out in the early fifties, Additional observations were secured at the Dominion Astrophysical Observatory, Victoria, B.C. in the summer of 1951. I attempted to make quantitative measurements of the emission line spectra of these objects and apply some of the methods developed by Menzel and his associates, as well as the Zanstra method to get electron temperatures, densities, and the temperature of the illuminating star. I proposed a model involving an extended attenuated envelope surrounding a binary system containing a cool supergiant and a hot source. [27] In collaboration with G. J. Odgers and A, McKellar of Dominion Astrophysical Observatory, McLaughlin and I worked on the 1951 eclipse of the remarkable supergiant 31 Cygni, wherein the analyzing beam from the B star companion serves as a probe for the extended envelope of the K—type supergiant star. [28] E. B. Weston, who was a graduate student at Michigan at the time, and I systematically observed T Tauri and one or two other similar stars to detect night to night spectroscopic changes. A summary of this work is described in one of the Liege conferences.

Unfortunately, the telescope was too slow and the dispersion too low to yield more than a broad overview of the changes. With the 24—inch Curtis Schmidt, I undertook a survey of the emission regions in Messier 33, measuring the Ha brightnesses with the aid of calibrated objective prism plates,[29] In 1952 at Mt. Wilson, I was able to examine some of the excellent direct photographs that Sandage had secured, These plates revealed the extreme complexity of many of the regions. I decided not to publish the material I had secured on the Schmidt plates, as I hoped to borrow or secure much better data. In 1954, Liller and I used his photocell and the objective prism on the Schmidt to measure the fluxes in Hb and the green (0111) nebular lines in a number of planetaries.[30] This was some of the earliest spectrophotometry on planetaries by photoelectric methods, Soon, thereafter Liller built a spectrum scanner which we used at Mt. Wilson and which I was able to use in Australia. Liller and I also observed the Orion nebula with the Schmidt and attempted to derive its chemical composition and compare it with those of B stars.[31] We found an electron temperature of 9000 degree K—a value not far removed from that which I had deduced in 1946 from the then available data. One of the biggest enterprises in which I was involved in Michigan was that by Goldberg, Edith Muller, and myself to determine the chemical composition of the sun.[32] We were able to use material obtained with the vacuum spectrograph at the McMath Hulbert Observatory. We used the best model atmosphere we could, along with an appropriate theory of spectral line formation, together with the best f—values we could get. It was the most systematic study that had been made since the time of Russell (1929) and did much to substantiate the similarity of the sola composition with that of carbonaceous chondritic metheorites.

Since then, observational material has been improved, f—value determinations have been greatly increased in accuracy, and the method of spectrum synthesis has been developed. An active theoretical program was also pursued. Marvin White and I attempted to compute collisional cross—sections for the 2p2 configuration of ionized nitrogen, reasoning that if the lines of (Nil) and (0111) originated in the same volume, we could use the auroral/ nebular line ratios of these two ions to solve simultaneously for both electron density and temperature.[33] We recognized at the time that the method might fail because N+ and 0-H- almost certainly are concentrated in different volumes. Alas, also, the collisional excitation theory we used was faulty and the suggestion could not be implemented for ion pairs until accurate theoretical collision strengths could be calculated, Fortunately, this problem was solved by Seaton in the early fifties. It is possible to choose ions which do originate in the same volumes and use this principle to deduce plasma diagnostics. Applying the ideas which Menzel and I had used in Ap.J. 94,30,1941, I examined afresh and in greater detail, the effects of collisional excitation on the cooling of a nebular plasma, employing more extensive observational data than had been available earlier.

A fair spread in electron temperatures could be understood in terms of varying amounts of coolants, and variations in the illuminating stellar fluxes.[34] One of the courses that I had to teach in Michigan was that in stellar structure (stellar evolution calculations were just barely getting underway). In the late forties, there was still the lingering possibility that the proton—proton reaction might not work as advertised and stars might have to run on the carbon cycle. Advances in beta—ray understanding showed that the p—p reaction was almost certainly OK and we had to construct stellar models with it as the energy source for low mass stars. Up to that time, the Cowling model of a convective core and a radiative envelope had been universally accepted. In 1951 our stellar structure class: Joe Chamberlain, E. N. Lewis, W. Liller, Jean McDonald, W. H. Potter, and Nancy Weber looked into this problem and we were able to show that no Cowling model would work with a proton—proton energy source. [35] Later (cf. Liege symposium 1959) we attempted to calculate models of helium stars in an effort to see if they would or could explain the nature of the central stars of planetary nebulae. These calculations were all done before the advent of modern computers, using the U—V plane and similar techniques as described in Schwarzschild’s book. After I left Michigan I did not again teach stellar structure except to undergraduates. In my later years at Michigan I had the good luck to be able to work with Sydney Chapman on problems of thermal diffusion, It is well—known that such effects are important in the solar corona and chromosphere, but they do not seem to be significant in gaseous nebulae.[36] The solar photosphere offered a more engaging problem.

Here, over the lifetime of the sun, the effects could be decisive, unless the outer layers of the sun were kept mixed — as they are by the convection zone. Observationally, there is no evidence of any settling out of the heavier elements. We must conclude that the thickness of the convective layer is close to that indicated by stellar structure theory. If it was too thin, effects of thermal convection would be manifest; if it were very thick, light elements such as lithium and boron would be totally obliterated.[37] Writing books was another diversion for this cloud—bound astronomer. The rough text written at Indiana finally appeared in published form in two volumes after numerous set—backs and frustrations.[38] Chapters on stellar atmospheres were also prepared for the Compendium on Stars and Stellar Systems.[39] An article on abundances was prepared for Handuch der Physik, but I expanded this theme in a brief summary of data from the earth’s crust, meteorites, stars, and nebulae.[40] My Harvard PhD thesis on the physics of Gaseous Nebulae had never been published, although a number of papers based on it had appeared in the series “Physical Processes in Gaseous Nebulae.” Theoretical advances and new observational data had appeared, including Olin Wilson’s slitless spectra of planetaries and Minkowski’s superb direct photographs obtained with the Hale telescope. Nancy Weber Boggess traced many of these with the isophotometer.

I decided to incorporate this material in a monograph which appeared in l956.[41] Thanks to the generous opportunities offered by the Mt. Wilson Observatory, I was able to continue the work on B stars that I had started there in the late forties. In (1946—48) I measured and made micro— photometer tracings of many coude spectra of B stars. Most of these plates had been obtained by Adams and by Merrill in their studies of interstellar lines, but were suitable for measurements of equivalent widths and line profiles. Results of a survey were presented in a review article prepared for Hynek.[42] Unfortunately, although of excellent quality, the plates did not cover important regions of the spectrum. I requested and was granted time in 1952 and 1955 to secure coude spectrograms for a good series of relatively sharp—lined 0 and B stars. The first papers of the new series involved an application of the curve of growth to € Canis Majoris[43], and a simple model atmosphere to 55 Cygni.[44] Fortunately, at this time, Gunther Elste came to the University of Michigan as a post—doc. Her, Jun Jugaku, and I applied the Pecker theory to a model atmosphere for tau Scorpii to interpret line intensities. High speed computers were not available, but Elste was very skillful in developing graphical methods. The Pecker method involves the calculation of contribution functions which take into account the weighting function for the continuum and each line, saturation effects etc.

It gives a vivid depiction of how different layers contribute to the formation of a line.[45] Next, Jun Jugaku and I applied this method to Pegasi for which I had obtained a series of high dispersion spectra a Mt. Wilson in 1952/55 — covering the spectral region from k 3200 to 6800.[46] Similar measurements were carried out for a number of other B—stars, including several stars of the Cephei type. List of wave—lengths, identifications, equivalent widths, and also line profiles are given in one of the last Publications of the Observatory of the University of Michigan. The theoretical treatment of the data: contained therein has been superseded. One feature of this investigation was an investigation of the profiles of the hydrogen lines, using a theory which tried to take into account the broadening action of the electrons as well as those by the ions. [47] Our emphasis on the broadening of the hydrogen lines came about as a consequence of Professor Otto Laporte’s development of the luminous shock tube. One of his students, Eugene B. Turner, showed how it was possible to produce Balmer emission lines under controlled conditions where you knew the plasma diagnostics and could measure the profiles. Another physics student, A. C. Kolb, became interested in the theory of line broadening. I was closely associated with the thesis work of these two research students, Kolb tried to take the electron contribution to the broadening into account and showed that it would be quite important. We immediately tried to apply these theories to the stars. Kolb went to the Naval Research Lab and worked for a while with Griem of Maryland to develop an improved theory.

Another student, Wilkerson tried to use the shock tube to measure f—values. During the Michigan years, most of my research work was associated in one way or another with Mt. Wilson, The guest investigator program which had been initiated by I. S. Bowen was a godsend to us observationally inclined astronomers in the east and Midwest. Much of my work was done in collaboration with staff members: Olin Wilson, R. Minkowski, I. S. Bowen, and Jesse Greenstein, Some was carried out with my colleague, Bill Liller, when he was a staff member in Michigan, and for some I was on my own. Olin Wilson had obtained some excellent slitless spectra with the coude spectrograph for a number of planetary nebulae; I worked with him in 1948 and 1952. We carried out an investigation of the structure of IC 418[48] and attempted to construct a spatial model. We also investigated the spectra of the nuclei of several planetary nebulae, These stars showed absorption line spectra and also emission features of the Of type. We compared the profiles of the H line in these objects with those in “classical” 0 stars and found a close correspondence that suggested similar stellar temperatures and surface gravities. Thus, in harmony with results obtained earlier at McDonald, it appeared that if you knew the temperatures of classical 0—stars you should be able to get those of planetary nuclei that showed similar absorption line spectra.[49] Minkowski and I carried out a number of projects. The most extensive involved photographic spectrophotometry of slit spectra obtained with the 1,5m and 2,5m telescopes for a few bright planetary nebulae,[50] I analyzed these data to obtain plasma diagnostics and chemical corn— positions.[51] The results showed that filamentary structure was very important, a conclusion in harmony with that found at about the same time by Seaton and Osterbrock who used the 3726/3729 (OII) line ratio, A special effort was made by Minkowski, Bowen and me to obtain a good description of the spectrum of NGC 7027.[52] We had only photographic methods available and attempted to compare spectral lines over an intensity range of ten thousand! This required obtaining a series of graded exposures, and comparing lines of successively lower intensity as one goes to longer and longer exposures.

In spite of all our precautions, systematic errors crept in with the consequence that the weaker lines were measured systematically too strong. This problem was finally solved in the seventies by a concerted effort by J. B. Kaler, S. J. Czyzak, H. Epps, and me using photoelectric scanners, the Wampler—Robinson image dissector scanner, and electronic camera data to replace photographic techniques as far as possible and to calibrate photographic data when we had to use them.[53] Measurement of very weak lines in nebular spectra has been a topic to which I have devoted much attention. Weak lines contain a great deal of information, but their intensities are difficult to get. From the abuse I have received from unidentified referees who conveniently hide under the cloak of anonymity I wonder if the effort is worthwhile.

With the aid of Seaton’s collision strength calculations, and using the methods employed in Menzel’s and my 1945 paper, I attempted to estimate the chemical composition of NCC 7027,[54] Minkowski and I made a new estimate of interstellar extinction, examined the role of collisional excitation, and suggested some re—interpretations of the spectrum.[55] Investigations by many observers, extending from the radio frequency range, through the infrared to the satellite ultraviolet have shown NGC 7027 to be an exceedingly complex object. Minkowski made outstanding contributions to the optical identification of radio sources. He had made a careful study of the spectrum of the radio source in Cassiopeia, where he found strong (Nil) and weak HCZ. We attempted a theoretical interpretation in which he envisaged a heated gas whose electron temperature was high enough to excite normal forbidden lines, but not the hydrogen lines.[56] No radiative source was present; the gas was heated by collisions between clouds or possibly shocks. In our paper on the Owel Nebula,[57] we pointed out the Ha-or Hb flux, together with the angular size and a reasonable assumption about the electron temperature, would put constraints on the distance if you assumed some value of the mass. In other words, we could exclude the distance suggested by Berman because it led to a mass larger than that of the sun.

We felt that there was a large uncertainty in the mass which would preclude using such a method to get distances. Subsequently, Skhlovsky, postulated a fixed mass for nebular shells and derived distances; he was unaware of our paper until we called it to his attention. In the summers of 1954 and 1956, Bill Liller and I made a number of photoelectric observations of planetary nebulae. In 1954 we used narrow band—pass filters similar to those he had employed in his thesis to get monochromatic nebular fluxes of the green nebular lines and H3.[58] In 1956 we used the spectrum scanner he had built to measure the spectra of a number of bright planetaries.[59] Also we detected the variability of the spectrum of IC 4997, in particular the steady decline of the intensity of4363 with respect to H which we interpreted as evidence for a decrease in density in an expanding nebular shell.[60] One of the more engaging programs involved metal—deficient stars. In 1949 Sanford loaned me plates of two so—called sub—dwarf A stars, RD 19445 and RD 140283, which Joe Chamberlain and I analyzed along with a normal A—star, 95 Draconis.[61] These subdwarfs turned out to be metal deficient; they were actually not A stars but G stars as indicated by the level of excitation. The strong hydrogen lines were due simply to the great transparency of the atmosphere; there were few metal atoms to supply electrons for the negative hydrogen ion. The paper was not greeted with acclamation in all quarters for there were those who still did not believe in metal/hydrogen ratios grossly different from that of the sun. We found that by stretching everything to the limit we could not get a metal/hydrogen ratio greater than 10% that of the solar value.

New data were needed. Jesse Greenstein obtained excellent spectra of these stars with the Hale telescope.[62] We found molecular bands in the spectra and were able to show that the value of the metal/hydrogen ratio was actually about 0.01. Independent measurements of the colors confirmed these conclusions for they showed that these objects were indeed G stars. The study was extended to red giants with extreme metal deficiencies by C. Wallerstein, R. Parker, H, L. Helfer, J. L. Greenstein and myself. I. S. Bowen also supplied spectra of gaseous nebulae which proved very useful for analyses, notably Orion and NGC 7662 which J. B. Kaler and I analyzed — although this work was actually carried out after I had moved to UCLA. With such opportunities as I had enjoyed in the fifties, particularly at Mt. Wilson, you might ask why I was seriously contemplating leaving Michigan, even in the teeth of Niehuss’ slur.

There were several factors: First as I have previously mentioned, the opportunities at Mt. Wilson were necessarily diminishing as more people wanted to use their instruments. Bowen, himself, had called me into his office one afternoon in 1959 to explain that while they would try to let me have some observing time in the future, I definitely could not count on having as much as I had in the past. Second, it was apparent that neither Goldberg nor McMath were interested in building up any modern instrumentation for stellar work (and this includes a telescope of adequate size in preferably a good location) that would be available for Michigan observers, i.e., that we could count on — come hell or high water, As far as McMath was concerned, it was evident that he had no interest in telescopic equipment for Michigan. His sights were set on much bigger things. Kitt Peak would offer a far more elegant vehicle for the glorification of Robert Reynolds McMath than anything at Michigan. So the big propaganda blast was that Big Brother at Kitt Peak will take care of all your telescopic needs. Third, when I brought this matter up at the National Science Foundation, and argued for places like Michigan to have their own telescope and adequate auxiliary equipment, I was told that all support was to be directed to Kitt Peak and if we wanted to do observational astronomy we could sign up for the queue — in essence place ourselves at the mercy of some faceless committee.

The hostile attitude of the University of Michigan top administration combined with the decision on the part of the National Science Foundation, as of that date — to put all their eggs in the Kitt Peak basket could mean only one thing. It meant that places like Michigan would be doomed insofar as they had to compete with newly developed places that had good modern instruments in excellent locations. When the Whitford report came out, suggesting small or medium sized instruments for various colleges and universities, the NSF modified their stand. Finally, Michigan got a 50—inch and Hiltner did a fine job of arranging for it to be moved to Arizona, where it has become a very effective instrument, But in 1960 and 1961 there was no indication that this was going to happen. Then and there I had to make a decision on the basis of the facts as they stood,

DeVorkin:

But it seems as though, since Michigan was one of the prime movers for Kitt Peak, that you would certainly have gotten telescope time,

Aller:

That doesn’t follow at all, because telescope time is assigned on the basis of judgments by committees, They are anonymous and can justify their decisions by the most absurd statements and unmitigated rubbish.

DeVorkin:

Would not this be the same way as NSF provides funds?

Aller:

Yes, by the judgment of referees, who are free to make scurrilous and irresponsible attacks on a person, to present absolutely phony arguments against a program, without the victim ever having a chance to defend himself. Let me give you an illustration drawn from recent experience. I applied for funds to go to Australia to work with Ross and O’Mara on supergiants in the Large Magellanic Cloud with the Anglo— Australian Telescope and the image photon counting system. The application was denied but my colleagues got the data anyway, we analyzed them at UCLA, and I was invited to present the results at the Montreal IAU meeting (the report will appear in Highlights of Astronomy). I asked to see the referees reports and they were sent to me. All but one contained some constructive, although not necessarily practical suggestions, but one was simply a vindictive attack, complaining about insufficient references etc. — not finding any fault at all with the science but arguing against giving support to an old guy who was nearing retirement — and anyway, most of the benefit would go to Australians and not to Yanks.

I inquired as to why the project had been rejected and got the reply that the essential reason was that it would benefit mostly Australians, not Americans. The actual facts are that of the ten people involved with me in this enterprise, nine were Americans (7 of them being students at UCLA) and only one, B. J. O’Mara, was an Australian! A phone call or a letter could have clarified this at once, but the NSF was not interested in anything I had to say in my own defense, My own belief is that I was condemned already and they were just looking for an alibi, an alibi that was nothing more than a clumsy insult. In summary, then, you are deprived of opportunities because you have no chance to defend yourself against curs who never come out in the open, but hide under the cloak of anonymity. All the NSF needs is one or two of these venomous, unsupportable attacks, to shoot you down, if they so choose, What I propose is that, before any decision is made, the applicant be apprised of the objections which have been raised and given a chance to present a rebuttal. The anonymity of the referee is kept sacrosanct, but the victim is given a chance to defend himself, Such a procedure is followed by the Australian Research Grants Committee, The final decision should then be made by a panel of competent scientists, I’ll admit that this procedure would be time—consuming and drag things out, but at least it would be fair — it would restore the most elementary principles of justice, a chance to respond to attacks before judgment is passed.

The present system would be like having the Grand Jury convene, draw up an indictment based on whatever was presented and then have the judge pass sentence without the victim ever being given a chance to speak. The NSF may have my name in their Black Book for another reason — a speech I gave at an AAS meeting in Mexico City against so—called “overhead,” which I described as blatant payola. Let me illustrate what I mean. During the summer, when I am not teaching I receive no compensation. I go to my office every day, do my research, write papers, crunch data on the PDP—ll, and try to catch up on the journals in the library, Or maybe, once in a long while I get a travel grant from the local UCLA research committee (as I did in 1979 to go to Australia to observe planetary nebulae in the Small Magellanic Cloud). All well and good. But suppose I have an NSF grant for summer salary, say $4000, and they were to give me $1600 for an air ticket to observe with the AAT in Australia. Then, lo presto, it miraculously costs as “overhead” about $2000 because I am working at the office doing exactly the same things as I was doing anyway — and it costs an “overhead” of $800 to do the paperwork for that roundtrip ticket to Siding Springs. And where does this $2800 go? In some places it might accrue to the department — not at our place, though. I’m not aware that UCLA gets any of it. In other places, the $2800 would be split fifty—fifty between some mysterious kitty and the state government. For suggesting that this system of what I call bluntly payola be reexamined so that more money might be available for research, I have been severely criticized. In passing, I might remark that the National Research Council of Canada and the Australian Research Grants Committee do not allow overhead, nor salary to the principal investigator who is supposed to be paid from his home institution. But to return to the question you asked about Kitt Peak, my basic objection is that their decisions are made by committees, against whose judgment one cannot argue.

DeVorkin:

In the case of Kitt Peak, though, is the committee really a confidential anonymous group?

Aller:

I do not know whether the membership is anonymous. The referees are anonymous. Program proposals are sent out and evaluated in some fashion and judgments are rendered. Any such system which operates through a cumbersome bureaucracy will result in injustices and inefficiencies. I think that the basic philosophy is a bad one, What one should do is to put support into institutions that are really trying to do something, and have demonstrated in the past a capability of accomplishing things, Kitt Peak’s job would be largely to take care of the people who are in small places with no equipment, or who are in larger places and need to use highly specialized equipment. Experience has shown that the number of active astronomers in the USA is too great for Kitt Peak to be able to take care of their total needs. The problem is that as things stand, you cannot plan a program with any assurance that you will get the time to see it through.

DeVorkin:

I see, and long term programs are out.

Aller:

Well, neither long term programs nor short term programs, perhaps. If one needs one observing run, you might have a chance, but even so, you might get clouded out, You can apply for time for a good or continuing program and may even be given time, But they may assign time to somebody else for exactly the same program. You may go down and get clouded out or have equipment trouble while your competitor lucks out. He publishes results and gets more time while your applications wither on the vine, A vivid illustration of what could happen if you placed yourself and your research programs at the mercy of a national observatory and its faceless committees was presented by my own experience at Cerro Tololo. This little episode shows just how well Kitt Peak would take care of all the needs of an observing astronomer, Czyzak and I had been observing HII regions in the Magellanic Clouds with the 36—inch and 60—inch telescopes at Cerro Tololo, We used photographic methods because no scanner was available. Naturally, we would have preferred to use a scanner as I had done in 1960/61 at Mt. Stromlo. In 1971, Malcolm Smith tried to help us get image tube observations, but it sparked and yielded plates that were photometrically useless — although they did indicate the extremely complex fine structure of the HII regions in the clouds.

When their scanner became available in 1972, I applied for time to try to do this program properly, Meanwhile, they assigned time to our competitors for the same program. In 1972 I got only one night; our competitors lucked out. In 1973 I had better luck but in 1974 clouds again spoiled most of the nights, and in 1975 as in 1974 I was denied time on the 60—inch, being given only nights on the 36—inch from just before Christmas through New Year’s Eve, We struggled along as best we could but there is no substitute for light gathering power. Meanwhile our competitors were given generous allotments of time on the 60—inch; they had much better luck with the weather than we had, Furthermore, they were able to use good image tube equipment, instead of the junk we had struggled with in 1971. In 1974 we were able to take some direct photographs with an image tube camera at the Yale 1 meter telescope, the platform for which could not be moved, One assembled an assortment of boxes and ladders but the telescope always became difficult to guide when you reached the awkward position. The scale of the plates secured with the meter telescope did not suffice to bring out the fine detail offered by the excellent Cerro Tololo seeing. In 1976 I submitted a proposal for a new spectroscopic program and a program of monochromatic photographs, both requiring larger telescopes than the 0,92 and 1.0 meter telescopes to which we had been exclusively assigned since 1973. I pointed out that we had done all we could with the small telescopes; we needed to observe fainter lines for nebular diagnostics, and secure better observations of small, faint HII regions.

I requested to use the vidicon system. We needed direct photographs with a large scale to push to the limit of resolution and to solve a particular problem that had been vexing us. In our photoelectric scans of 30 Doradus, Faulkner and I had concentrated on a bright arm near the core. The Peimberts chose the same area, as did we in 1973. Our observations agreed in showing that the helium/hydrogen ratio was lower than in our galaxy. Was this result real or was it simply an artifact of incomplete helium ionization in a spot where hydrogen was still completely ionized. High resolution direct photographs could tell, because monochromatic images in helium would show a thinner arc than those in hydrogen, Plates taken with the Yale 1 meter telescope were indecisive, One needed the scale of the 4 meter telescope. My request was turned down cold, I was told that my competitors had done better work with fewer trips. In fact, we had been restricted to the 0.91 m telescope after 1973 because of our poor record of accomplishment. The outstanding competence and profound knowledge of the committee was illustrated by the remark that we did not need to come to the southern hemisphere to work on 30 Doradus; we could work on a similar object in the northern hemisphere!

The letter was written in a tone that one might expect of a tactless reprimand to a marginal graduate student, To all of this, I wrote a rather lengthy but dignified reply — giving the background of our program, and explaining en extenso the bad luck we had had with the weather, citing the nights wasted with a junk image tube and inefficient spectrographs. As for our competitors, they being good astronomers, blessed with good weather, larger telescopes than we were permitted to use, and equipment that worked well, certainly must have accomplished more, I still thought that we had a good program of direct photographs and spectroscopic work, (As far as monochromatic studies were concerned, nobody at Cerro Tololo ever carried out the program we had proposed. In fact, it was done by Meaburn and his associates of University of Manchester who showed the bright arm in 30 Doradus to represent an ionization front). Director Blanco wrote a very considerate, courteous, letter in reply. The committees made the decision and there was nothing he could do about it. When I applied for time in 1979 to work on planetaries in the Large Magellanic Cloud with the 4 meter, I received a lovely Christmas present of four nights; evidently my protests had not done any harm.

Just for fun, I send the documentation on my 1976 time request to Leo Goldberg. He sent back a very terse note with not one single remark on the points that I had brought up. Rather, he simply said that in a national observatory these decisions have to be made by committees; maybe I’d have better luck next time. That was all. It is fitting that Leo himself demonstrated by this letter the validity of the objections that I had raised so many years before, I recognized the argument that Kitt Peak would take care of all our observing needs as a bill of goods, as a snare and a delusion. Nor was I the only one. Helen Dodson Prince of the McMath Hulbert Observatory saw the ominous possibilities even more clearly than I did. I remember her remark to the effect that Kitt Peak could well be the finish of places like Michigan.

DeVorkin:

How is the situation different at the University of California as far as use of the Lick Observatory goes?

Aller:

There is a committee that passes judgment on programs and assigns time, but every campus has a representative so he can defend your program for you if you think it is a good one and can convince him of it.

DeVorkin:

Would it be better if Kitt Peak gave applicants a chance to defend their programs?

Aller:

I think it would be. Admittedly they would squawk that it would be more cumbersome, but I think a person ought to have a chance to defend his work, as I have outlined above.

DeVorkin:

Was this a monolithic decision, in the construction of Kitt Peak and in its operation?

Aller:

I know nothing about the development of Kitt Peak because I’d been banished to the outer darkness, All these decisions are made by the inner circle.

DeVorkin:

Who is the inner circle?

Aller:

:1 don’t know who they are.

DeVorkin:

I mean in the beginning.

Aller:

At the outset, the NSF had a panel on general program support. Later a panel was organized to develop Kitt Peak. I don’t know anything about it because I was not involved. Frank Edmondson is the man to consult about all this. I really cannot say much about Kitt Peak; I never observed there. By the time it got rolling, two things had happened; I’d gotten deeply interested in the southern hemisphere and then I joined the staff of the University of California, Los Angeles. Shortly before Goldberg announced that he was quitting Michigan to accept an offer from Harvard he could not refuse, I had made plans to go on a sabbatical to Australia.

DeVorkin:

Was this your first trip?

Aller:

Yes, this was my first trip to Australia. By time of Goldberg’s announcement, all the arrangements had been made, I’d gotten a fellowship from the National Science Foundation and support from the Australian National University. All the paperwork had been done. Suddenly Leo said to me one day: “You’d better postpone that trip and stay here and look after the students. Otherwise there may be none here when you come back!” Suddenly he seemed to be so solicitous about the students. As for the implication that I was the indispensable attraction, it impressed me as pure flattery. I replied that I would not postpone the trip — shorten it maybe but not postpone it. I’d given my word that I would go and I intended to live up to it, And so I did go — for the entire year. The students did not disappear.

There were more of them there when I returned than when I’d left. This was to use the equipment at Mt. Stromlo, Bart J. Bok was director there and he did everything he could to make my stay a memorable one. I took Liller’s scanner with me, Putting that instrument on a telescope and directing it to the treasures of the southern sky was one of the most thrilling episodes of my life, I know how the naturalist, Banks, must have felt when he landed with Captain Cook in Botany Bay two centuries ago. A young graduate student from the University of Queensland, Donald J, Faulkner, was assigned to work with me, He was a very capable fellow and a hard worker, but I must have driven him too hard because he turned to theoretical work afterwards, The scanner was equipped with a blue sensitive cell so we could not get beyond about7L6000A. Thus, it was not possible to get Ha and (NII). We could go down to 3000A at the 74— inch which was an f/5 aluminized reflector. For the other telescopes we had to use an adapter in the optical system. At Mt. Stromlo we worked mostly with the resurrected 50—inch Melbourne reflector, which Woolley had bought essentially as scrap and had reconstructed with a sturdy mounting and a glass mirror.

The telescope still had the beautiful silvered setting circles! It tracked well and we got some thrilling results with it. We also observed with a 26—inch reflector at an observing site west of Stromlo, near Griffith, which was called Mt. Bingar. Most of our effort was devoted to 3 principal programs: (a) energy scans of bright stars to determine relative flux distributions, (b) planetary nebulae in our galaxy and HII regions in our own galaxy and the Magellanic Clouds, (c) star clusters and special objects such as eta Carinae. I’d like to describe each of these programs briefly in turn. We measured the energy fluxes in a well—distributed sample of southern early type stars, by spectrophotometric intercomparisons. The final reductions were carried out in collaboration with R. H. Norton at the Jet Propulsion Laboratory. We adopted as standards, stars on our list whose energy distributions had been measured by Oke and solved for F(l/?j by setting up a photometric network, analogous to geodetic networks of surveyors.[63] This effort constituted the first systematic effort to establish energy distributions in southern stars. Faulkner and I also devoted special attention to a number of individual objects, among the Velorum, for which we obtained a color temperature of 30,000 degree K.[64] Our main effort was devoted to HII regions in our galaxy and in the Magellanic Clouds. We made a special effort to measure the He/H ratio in the brightest HII region, NGC 346, in the SMC. We found a smaller ratio than in our own galaxy— a value in good agreement with those found by subsequent workers.[65] Faulkner’s PhD thesis was on 30 Doradus and the p’— Carina nebula, we gave a description of the spectra, and attempted to evaluate plasma diagnostics and chemical compositions as far as possible.[66] We concentrated on the bright arm near the central star cluster in 30 Doradus and found a He/H ratio in good agreement with the later found by Peimbert.

Since we are limited to wavelengths shortward of...60OOA, we could not estimate the abundances of sulfur, nitrogen, or argon. Less complete data were secured for other HIT regions in the LMC and SMC, since for these objects we used mostly the 26—inch telescope at Bingar. Mrs. Dickel at Michigan collaborated in the analyses of these data — determination of fluxes and intensities for the brighter lines.[67] Also I secured a number of direct photographs in Ha radiation of a number of HIT regions in the LMC, using the Newtonian focus of the 74—inch. Mrs. Dickel analyzed these plates for her thesis. Faulkner and I were able to pioneer photoelectric spectrophotometry of a number of planetary nebulae in the southern Milky Way, some of which Ross, O’Mara, and I have studied with the AAT and the IPCS recently. Unfortunately, we were able to cover only the blue spectral region, 32OO — a5lOOA.[68] We also secured energy scans for several globular clusters, including 47 Tucanae, w Centauri, and several objects in the LMC. We compared these energy scans, which corresponded to the integrated light of these clusters with individual stars, trying to find the stellar spectra that most closely matched the clusters. It was indeed possible to establish equivalent spectral classes to compare with integrated colors.

The solar—like metal/hydrogen ratio of 47 Tucanae, and the low metal/ hydrogen ratios of certain other clusters were well revealed by these measurements. [69] Of course, special attention was paid to Carinae itself with the scanner. Near the end of my stay at Stromlo, Theodore Dunham had succeeded in getting the coude spectrograph into operation. We were able to secure several plates and give a quantitative description of the spectrum. [70] Director Bok and the staff of Mt. Stromlo were helpful in every V way and made my year in Australia a very productive one. What a fool I would have been to have given it up to remain that year in Michigan, especially since Mary. Niehuss had convinced me that I should leave if I could get a good offer elsewhere. While 1 was in Australia, I received three serious inquiries, one from Texas, one from the University of Chicago and one from the University of California — all of them offering opportunities to work with large modern telescopes. Since I was on sabbatical, I was obliged to return to Michigan for one year, which I did, but on October 17, 1960; I accepted an appointment to UCLA.

Although I felt that the attitude of the NSF towards instrumentation at individual universities and the hostility of Mary. Niehuss left me no other choice, I left Michigan with deep regrets. With the possible exception of l’eminence gris, everyone with whom I’d been associated had been congenial and cooperative. The association with D. B. McLaughlin had been particularly productive. We had similar interests in astronomical spectroscopy: he has a vast store of expertise and knowledge on the subject. His death in 1965 made me feel very sad. Freeman Miller, who was in charge of the Schmidt had been very friendly and helpful. I was well aware of the great contribution made by Hazel Losh, who carried most of the elementary teaching burden in the department. Although I had less direct contact with Orren Mohler and Helen Dodson Prince at Lake Angelus, they supplied much encouragement and direct help — especially when I was writing my book on the atmospheres of the sun and stars. Fred Haddock was a valuable colleague, who brought in expertise in an important new field. The younger people, Don Wentzel, Bill Liller, Bill Howard (and before them Bauer and Wyatt) all con— tributed to an atmosphere of congeniality and cooperation, Goldberg, it must be noted had done a fine job in building up a staff, He had brought in Fred Haddock and started a program on radio astronomy with an 85 foot dish and he had started on a promising space research endeavor when the administration pulled the rug from under his feet. Bleak as things looked in 1960, I think Michigan is now doing very well. Moving the Curtis Schmidt to Cerro Tololo was a brilliant idea. They acquired a 50—inch which is now doing excellent work at Kitt Peak; under Hiltner’s inspiration they have built up some superb equipment. They have some excellent people on their staff — the Cowleys in stellar spectroscopy, Kirshner, who works on supernova remnants, to mention just a few of many.

DeVorkin:

I’d like to follow up on the origins of the 92—inch disk that Heber D. Curtis obtained from Corning.

Aller:

Curtis was brought to the University of Michigan about half a century ago, with the express purpose of designing and building a large telescope for the University of Michigan. It was recognized then by members of the staff, as apparently it was not recognized later, that in order to have a viable astronomical program, you had to have guaranteed access to a large telescope, The original plan, to put it in Michigan, could be criticized, but it was modified later, I first met H. D. Curtis when he gave a colloquium at Berkeley in the thirties. He remarked that the job of an observatory director was primarily to keep a roof over the heads of himself and his subordinates, He seemed to be a kindly, rather conservative gentleman, whose single—minded devotion to this project can’t be questioned.

He was also a capable instrument designer. After, he had become director, and was engaged in drawing up plans for the new telescope, the depression descended on the world - and the USA in particular, The legislature rescinded its appropriation for the instrument. There was no such thing as the NSF in 1930; the funds had to come from the state, and when this support was withdrawn he tried to find a private donor, I read the files, which were stored in the dome in the early fifties, I’d read them when the sky would cloud up and I’d have to wait for a break in the weather, The tone of the letters was often pathetic. He had no success in lining up a donor, At one stage he thought he could build the telescope relatively cheaply by engaging the services of a bridge—building company with which his brother was associated, There followed a long discussion. The bridge builders were willing to attempt the dome, but the telescope itself frightened them, Curtis tried to allay their fears but it was all shadow boxing. The last letter in this particular file is from the bridge company; it remarks that they have spent much time and money looking into this proposal, but unless some realistic prospects of funding are found, they can do no more, Curtis did succeed, however, in getting a pyrex disk from Corning. It was brought from the Corning works and laid in a tin shack beside the observatory building in Ann Arbor, By 1940, Curtis had realized that Michigan was not the place for a large telescope and he wrote Director Wright of Lick Observatory about the possibility of developing a joint University of California University of Michigan plan.

The idea (which was set forth not any later than 1940 or 1941) never 1 or 2 exchanges of letters. This proposal apparently died with Curtis, for when the new administration took over, the idea of a big telescope was suppressed. Instead, they opted for a 24—inch Schmidt camera which was to be a duplicate of the Case instrument. Funding was obtained from a private foundation (I think the MacGregor Fund — in which Judge Hulbert had much influence). One aspect of the deal was that title for the 92—inch disk reverted to this foundation. In 1950, Sir Harold Spencer Jones, the Astronomer Royal, appeared. McMath saw to it that this disk was given to him because “Michigan was no place for a large telescope.” (Note that Curtis’ idea for a cooperative project to put the telescope in a good location was conveniently forgotten). Thus, Curtis’ disk became the mirror for the Isaac Newton Telescope, which sits in the meadows of southern England, and from which the University of Michigan drew no benefit. The decision to give the disk away for a telescope in a miserable location was made by the top brass. Nobody on the Michigan staff was ever consulted with respect to the disposal of this disk, We were given no chance to discuss the possibility of using what had been our own disk in a cooperative program. Instead, it was given away, allegedly because Michigan was no place for a large telescope. Obviously, Brighton was so much better!

DeVorkin:

You left Michigan and spent a year in Australia, It must have been a pleasant time for you there, Was there any chance you could have stayed in Australia?

Aller:

It was a very pleasant place, but the answer to your query is no.

DeVorkin:

Why not?

Aller:

What would I have lived on? Nobody ever made me any offer, (I’ve heard so many silly rumors about my being offered a job in Australia. One day at lunch at Mt. Wilson, Visvanathan asked me “Why did you turn down the directorship at Mt. Stromlo,” I was flabbergasted at the question but I replied to the effect that maybe I didn’t assume the directorship because — not only was it never offered to me, but my name was not even on the list. I asked him where he had heard this nonsense and he said it was a rumor that had been circulating on the mountain - evidently planted for God knows what purpose).

DeVorkin:

I know that you have always been interested in southern hemisphere work?

Aller:

Yes, but that doesn’t guarantee a man a job. Gerald Kron was always interested in the southern skies, He did very good work down there, but as far as I know he was never offered a job. I’ve spent three sabbaticals in Australia, The second, 1968—69 was spent in Sydney at the University of Sydney and at Radiophysics C.S.I.R,O. and in Hobart at the University of Tasmania. I had a senior NSF postdoctoral fellowship. My third sabbatical 1977—78 was spent at the University of Queensland, where the physics department was able to provide me with a research fellowship. In 1968—69 I worked with the Mills Cross at Molonglo (near Canberra) and with the 64—meter dish at Parkes. In 1971 and 1977—78, 1 again worked with the Parkes dish on a cooperative program with Douglas Milne. In 1968—69 I did not optical observing, but fortunately in 1977—78 and 1979, I was able to do some optical astronomy — mostly with the Anglo—Australian Telescope at Siding Springs.

In 1967, I’d arranged to go to Sydney to work on radio astronomical observations of gaseous nebulae. At the IUE meeting in Prague, I met Olin Eggen who had been appointed director at Mt. Stromlo in 1966. I told him of my plans to be in Sydney and explained I’d like to do some observing with the coude spectrograph to complete some work that Dunham and I had initiated. Eggen lost no time in making it clear to me that I would not be very welcome, He said he did not think there would be any time for me since Alan Sandage was coming down, but I replied that Sandage would hardly be interested in moonlit nights. After Eggen got home, he wrote me from Australia to the effect that he could not offer me any encouragement to come to Mt. Stromlo, but if I was coming to Sydney I should send my program to Leonard Searle, now of Hale Observatories, who was in charge of such matters, Accordingly, I sent the program to him and he replied that it had been turned over to the appropriate people on the program committee and that I should be hearing from them soon. When I arrived in Australia, I was confronted with the allegation that my time request had never been received — so I did not get any observing time. Searle insists that he had received my time request and that it had been forwarded to the committee, So you can draw your own conclusions, Anyway I realized that I was not welcome at Stromlo as long as Eggen was director there.

DeVorkin:

Why was that? Was it something going back between you two?

Aller:

I cannot understand his hostility for I do not recall ever doing anything to offend him, nor was I ever a party to any disparagement of his work, One possibility is that he knew I was a good friend of Harold Weaver’s. Maybe that sufficed to damn me.

DeVorkin:

Oh, they didn’t get along?

Aller:

Gawsh no! There was a terrible feud there, I do not want to discuss it, Anyhow these things seem to be much better now. Eggen left Stromlo in September 1977 to accept a job at Cerro Tololo where he seems to be very happy. In 1978 I had a couple of observing runs with the 74—inch, working in collaboration with Sue Simkin. I found the atmosphere there to be very congenial. In this narration, I’ve left out everything pertaining to my personal life since I left camp, and my work and experiences at UCLA. My wife, Rosalind, got her ND degree from Indiana University in 1948, but she raised a family instead of practicing. Our oldest son, Hugh, is a radio astronomer at University of Michigan, our second son, Raymond, is an ND — a pathologist at Santa Barbara. Our daughter and her husband prefer the open life of the foothills of the Sierras. The UCLA days are still on-going. Life has been congenial and productive as well, I trust. Perhaps, a discussion of this — the present epoch — had best wait until later.

DeVorkin:

In the last few minutes remaining to us, could you give me an overview of. your feeling and opinions about the present state of astronomy.

Aller:

First of all, I would like to comment on the vast changes that have occurred in my lifetime, which are probably greater than in many previous generations of astronomers. When I was a student, I was taught to use a filar micrometer to make eye and ear observations with a transit instrument or meridian circle, and to compute the orbits of comets and asteroids with logarithms. The prism spectrograph and the photographic plate constituted the most advanced technology that any of us used. At the present time, I’m not using any of the techniques that I learned as a student — not one! Now we record spectra with image tube scanners, with the image photon counting system (IPCS), with a vidicon, with a multistage image tube like the shectograph, or a reticon. The data goes on computer tapes and can be manipulated in fashions never dreamed of in the old days of photographic work. We can subtract the sky from the image and if the exposure time is not long enough we just take another scan and add it to the first, All the data goes onto computer tapes and has to be massaged and manipulated from there on in.

I find this pretty tough as I’m pretty dumb when it comes to computers. The modern generation takes to all of this like a goose takes to a pond, My three year old granddaughter is learning about computers before she goes to kindergarten. It is very different from the way it was with Walter 5, Adams, Paul Merrill, and people of that generation. When they were young they learned how to measure and reduce spectrograms; they used essentially the same technique all their lives. It even became a little simpler when a grating replaced the prism as the dispersing element, We have seen a complete revolution in the acquisition of data, from a nineteenth century telescope where you cranked the dome around and manipulated the instrument by hand, to the 64m Parkes Radio dish, the Anglo—Australian Telescope (which can be set to 1’) or the International Ultraviolet Explorer, to mention three modern instruments, Theoretical advances have been staggering. Much of it has been possible because tedious arithmetic has been taken over by the computer, but most of the advance has been in new conceptions and insights in the nature of matter and radiation. Compare, for example, the Eddington “Standard Model” which was the going thing when I started to study astronomy with a modern evolutionary code that tracks a star through its later life as a giant or supergiant or follows the details of a supernova detonation, As we well know, all of this has brought enormous areas for research and it has inspired the imaginations and aspirations of great numbers of very fine, capable, young people. This has been a great thing because it has brought into astronomy and astrophysics many first—rate intellects, but alas there is another side to the coin.

What I find really heartbreaking is the great number of these eager, decent, conscientious people who would like to make contributions to our science, but are denied the opportunity to do so because of grievous limitations in funding and the consequent lack of jobs. Some drop out early in the game. Others get post—docs and may drift from one post— doc to another without ever attaining a permanent job in science. It used to be that after a young person had attained a PhD at a good institution, a post—doc was just what was needed to insure the offer of a good position promising permanence. But no more. Many come to the end of the line, approaching middle age without any job they can count on — and have to drop out, Many find jobs that have nothing to do with astronomy. Others find that some facet of their training has provided them with a marketable skill, computing programming for example. I think this was a grievous blunder that was made back in the sixties, Then there was a tremendous pressure to develop graduate programs in astronomy in all kinds of places. At that time, I raised the question as to what we were going to do to provide opportunities for these people. At the time I was thinking in terms of telescopes and equipment, and while there remains a terrible shortage of telescopes and equipment, that of jobs is even more serious.

The answer which was always hurled back at me was “we need these people to respond to the challenge of the space age.” Well the space age has come and largely gone, and there is a threat that it may be even further gone before long. So the job opportunities are not there. Astronomy, as such, does not have immediate utility in industry as does physics, But the vast numbers of young people we have lured into the field and have trained are still there. Many of them feel that they have been deceived; most of them feel frustrated, Another thing which I have noticed is that the spirit of comradeship and cooperation among astronomers has largely vanished, to be replaced by a dog eat dog atmosphere. Competition for jobs and funds is so keen that many seem to feel that anything they can do to win is OK, even if it requires poison pen and knife—in—the—back tactics. Anecdotes filter in from many quarters. Olin Wilson once offered me the consolation: “Let's be glad, Lawrence, that we were in astronomy while it was still fun.” The wastage of the skills and talents of our capable young scientists is a disgrace to the world.

The resources exist to put them all to work doing constructive things. Instead of that the substance of the earth is expanded on frivolities, on all kinds of power wasting devices and gas guzzling cars. Worst of all is the expenditure of technical expertise, energy and money on the arms race. Despite the wherewithal to wipe man off the face of the earth, ten times over, there is clamor to squander even more. Apparently, we want to do the job right, and insure that we guarantee the world to the cockroaches. As I looked at the crumbling walls of Constantinople, I reflected that they had protected the people of that city for hundreds of years before it fell in 1543, but when nuclear weapons are set in action, all the money spent on “defense” won’t protect the people of the world for a hundred days, a hundred hours, or even a hundred minutes! Nuclear war is universal suicide. The problems facing the human race, anyway, are horrendous. We need all the talents and skills of our young scientists, It may be that even under greatly improved circumstances, not all who wish to do so can find employment in astronomy, but at least they can use their scientific training for something constructive. But as we look around it would seem that the omnipresent characteristic of world leadership today is its gross incompetence and stupidity. Perhaps a miracle will occur. Let’s hope so, It is our only chance for survival.

DeVorkin:

Thank you very much.

[1]Publ. Astron. Soc. Pacific, 47 (1935), 327-328

[2]Astrophys. J. (1938), 87, 53-67

[3]Astrophys. J. (1942), 95, 5-23

[4]Astrophys. J. (1942), 95, 52-57

[5]Astrophys. J. (95), 73-75, (1942)

[6]Astrophys. J. (1938), 313-318; 422-428

[7]Astrophys. J. (1939), 89, 587-593; 90, 271-280; 601-610

[8]Astrophys. J. 93, 178-193, 1941

[9]The observational data on which many of these calculations were based are given in Astrophys. J. 93, 236-243, 1941

[10]Astrophys. J. 93, 195-201, 1941

[11]Astrophys. J. 93, 230-235, 1941

[12]Astrophys. J. 94, 30-36, 1941

[13]Astrophys. J. 96, 321-343, 1942

[14]Astrophys. J. 94, 436-448, 1941

[15]Astrophys. J. 97, 135-165, 1942

[16]Astrophys. J. 113, 125-140, 1951

[17]Astrophys. J. 107, 281-286, 1948

[18]Astrophys. J. 105, 131-150, 1947

[19]Astrophys. J. 102, 239-263, 1945

[20]Astrophys. J. 109, 42-52, 1949 (Aller, Ufford and Van Vleck)

[21]Publ. Astron. Soc. Pacific, 58, 258-260. 1946

[22]Astrophys. J. 106, 76-85, 1947

[23]Astrophys. J. 104, 347-356, 1947

[24]Astrophys. J. 108, 462-275, 1948

[25]Atmospheres of the Sun & Stars, NY, Ronald Press Co. 1953 Nuclear transformations, Stellar Interiors, and Nebulae, 1954

[26]Astrophys. J. 114, 145-151, 1951; 116, 184, 1952

[27]Publications Dominion Astrophysical Observatory, 9, 321, 1953

[28]Nature, 169, 990, 1952

[29]See the charts in ASTROPHYSICS II, p. 223 and in my Gaseous Nebulae p. 9

[30]Astrophys. J. 120, 48-57, 1954

[31]Astrophys. J. 130, 45-56, 1959; see also LHA Publ. Astron. Soc. Pac. 58, 165, 1946

[32]Astrophys. J. Suppl. 1-138, 1960 (Nr. 45)

[33]Astronomical Journal, 1949, 54, 181

[34]Astrophys. J. 118, 547-554, 1953

[35]Astrophys. J. 115, 328, 1952

[36]Astrophys. J. 127, 797-798, 1958

[37]Astrophys. J. 132, 461-472, 1960

[38]Astrophysics I, Atmospheres of the Sun and Stars (1953); Astrophysics II, Stellar Structure, Nuclear Transformations & Nebulae (1954) Ronald Press Co., New York. Originally the contract was with Blakiston which was absorbed by Doubleday who then repudiated the contract, in spite of the fact that the editor in charge agreed that I had fulfilled every request he had made to me to revise and shorten the text. A revised edition of Atmospheres of the Sun & Stars was prepared (1959-1961) & published in 1963 by Ronald Press. The second volume was never revised, although much of it quickly went out of date.

[39]Stellar Atmospheres, vol. 6, ed. J. L. Greenstein 1961 Chicago University, of Chicago Press, pp. 156-259

[40]Abundances of the Elements (1961), NY Interscience

[41]Gaseous Nebulae, 1956, New York-London, Chapman and Hall and Wiley

[42]Astrophysics, A Topical Symposium, (1951) ed. J. Allen Hynek, NY McGraw-Hill

[43]Astrophys. J. 123, 117-132, 1956

[44]Astrophys. J. 123, 133-142, 1956

[45]Astrophys. J. Suppl. 3, 1-33, 1957 (Nr. 25)

[46]Astrophys. J. 127, 125-142 (1958), Ap. J. Suppl. 4, 109-156, 1959, Nr. 38

[47]Astrophys. J. 128, 616-632, 1958; 130, 469-472, 1959

[48]Astrophys. J. 114, 421-430, 1951

[49]Astrophys. J. 119, 243-252, 1954

[50]Astrophys. J. 124, 93-109, 1956

[51]Astrophys. J. 125, 84-101, 1957

[52]Astrophys. J. 122, 62-71, 1955 (Later Bowen, O.C. Wilson and I made an effort to extend the coverage to the near ultraviolet spectral region 3100-4000; Astrophys. J. 138, 1013, 1963) Photographic photometry was used for the weaker lines; the stronger lines were measured photo-electricity

[53]Astrophys. J. Spl. 31, 163-186, 1976

[54]Astrophys. J. 120, 401-412, 1954

[55]Astrophys. J. 124, 110-115, 1956

[56]Astrophys. J. 119, 232-237, 1954

[57]Astrophys. J. 120, 261-264, 1954

[58]Stars and Stellar Systems, 7, 495, 1968, ed. B. Middlehurst and L. Aller, Chicago, University of Chicago Press

[59]Proc. Natl Acad. Sci. U.S.A. 1963, 49, 675

[60]Sky & Telescope; 16, 222, 1957; Mon. Not. Roy. Astr. Soc. 132, 337-345, 1966

[61]Astrophys. J. 114, 52-72, 1951

[62]Astrophys. J. Suppl. 5, 139-186, 1960 (Nr. 46); Astrophys. J. 137, 280-300, 1963; (Orion nebula) Astrophys. J. 141, 912-922, 1965; (NGC 7662) Astrophys. J. 144, 291-304, 1966

[63]Astrophys. J. 140, 1609-1612, 1964; 144, 1073-1100, 1966

[64]Astrophys. J. 140, 167-172, 1964

[65]Publ. Astrom. Soc. Pac. 74, 219-222, 1962

[66]Mon. Not. Royl. Astr. Soc. 130, 393-409, 1965

[67]Galaxy and Magellanic Clouds, IAU-URSI Symposium Nr. 20, ed. Kerr. F. and Rodgers, A. Canberra, Australian Acad. Sci. 1964, 294-309

[68]IAU Symposium Nr. 20, 1964, 45-49

[69]IAU Symposium Nr. 20 1964, 358-370

[70]Proc. Nat. Acad. Sci, USA, 55, 671, 1966; Astrophys. J. 1966, 146, 126-141