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Interview of W. Kent
Ford, Jr. by David DeVorkin and Shaun Hardy on 25 October 2013,Niels Bohr Library & Archives, American Institute of Physics,College Park, MD USA,www.aip.org/history-programs/niels-bohr-library/oral-histories/43241
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This interview is a biographical profile, an institutional history, and a focused study of examples of W. Kent Ford's electronic image amplifiers and detectors. The interview took place in the library of the Department of Terrestrial Magnetism that exhibits some of these instruments.Ford also brough several as illustrations during the interview. Portions of the interview were video recorded and are so indicated in the transcript.The interview is generally chronological, starting with his description of family life in Clifton Forge, Virginia that centered on his grandfather's enterprise, the Western Power Company, and other businesses in the town managed by his family.Topics include his pubic schooling, then boarding school, then training at Washington and Lee and graduate work at the University of Virginia. Discusses his mother's background and how he became interested in science. Describes how he came to meet Merle Tuve from the Department of Terrestrial Magnetism (DTM), and how he was soon hired as a summer assistant to participate in the technical development of thin films for photoelectric image recording.After graduation, Ford returned to DTM with a thesis based directly on his thin film work, which he continued on the Carnegie Image Tube Committee.There is much discussion on the history of the Committee, and Ford's participation in instrument development and contact with other members like William Baum, John Hall and others. Discusses development of electrostatic image tubes and testing at observatories in Ohio, and Flagstaff, Arizona, and then specifically describes instruments he brought with him for the interview emphasizing the technical details in their designs, what worked, what needed improvement.Throughout there is discussion of both personal and professional milestones: contact with astronomers at many observatories, how he met and married his wife, and settling in Washington. There are also discussions of contacts with industry, including RCA, Westinghouse, and ITT.Discussion then focuses on contact with Vera Rubin. How they deliberated over applications of the image tube technologies, settling on galaxy rotation curves, and how they designed their program, developing an off-set guiding system for the DTM image tube spectrograph. Describes and discusses the instrument in some detail and recommends how we should modify its display. Discussion of computers at DTM, how they changed over the years, and their role in ushering in digital detectors like the CCD into astronomy.
This is an oral history interview with W. Kent Ford. And, the W is for William?
And, I’m a junior. I’m W. Kent Ford, Jr.
The date is October 24th. We are in the Carnegie Institution Library, Carnegie Institution of Washington [Department of Terrestrial Magnetism] Library. In the room, Shaun Hardy, and David DeVorkin. And, the auspices is the Carnegie.
We know you were born April 8, 1931 at Clifton Forge, Virginia. And, what we would like to do is start out learning a little bit about your family life, who was W. Kent Ford, Sr.? What his background is, and your mother, and what your home life was like?
Okay. I’m going to throw you a curve, right now. Clifton Forge was a railroad town. C&O Railroad had a division point there, and had a hospital, and machine shops, and all kinds of good things. The curve is that the family settled there in the 1890s. My grandfather, who was born in 1876, after the war, the Civil War, came as a twenty-year-old and opened up a greens grocery. He had very little money, but he started a grocery store in downtown Clifton Forge.
And, his name?
Ambrose Carrington Ford. As time went by, he needed ice. And so, he and a partner opened up an ice plant. And, as more time went by they needed refrigeration of other sorts, and he put in a generator and started an electrical system, and an electrical system for the town of Clifton Forge. That early system developed to something called the Western Power Company, with its offices in Clifton Forge, and my grandfather was president. And, they extended from Ronceverte, West Virginia, through Covington, Clifton Forge, and east into Lexington, I believe. It was quite a company, and in 1925 my grandfather and his partner sold the company and got their money out just before the great crash, 1928. My father did not graduate from college. He started out at Virginia Military Institute in—well, I’m not sure of the year, but probably 1915-16. After two years, he went into the Army and sat out the war in northern Vermont, northern New York state, Plattsburgh, New York. When he came back, he had a year or two of additional college, but he had studied engineering and he, even though he did not have a degree in engineering he had an engineering background. So, he started putting up the transmission power system for my grandfather’s company. He ran the power lines from West Virginia through our part of Virginia.
Later, he became an engineer with the infant Douthat State Park, which is located near Clifton Forge, and was very much involved with the organization, the building of the dam, and the building of the facilities at the state park. He went from there into the National Park System, and we lived in Richmond, briefly, and in Cincinnati, Ohio.
Why did you move around?
In the National Park Service, you don’t stick in one place. It’s like the military service. And, I think my mother and father did not appreciate that. And so, they left the Park Service in 1936 and came back to Clifton Forge.
By then did you have brothers and sisters?
No. I’m the only child.
Okay. Is there any reason for that that you want recorded?
None that I know of.
Okay.
There’ve been various jokes. My small boy comments. When my childhood friends would have siblings coming along I would make some silly comment, like, “I think I’m better off single.” (Laugh) As a five-year-old.
Yes. There’s always that concern.
But, I have no idea.
Possibly it was their moving around a bit. But then, they decided they had to stabilize?
I think that they both were quite fond of Clifton Forge, which is really a quite nice small town. Population 5,000. It’s been population of 5,000 ever since I can remember. (Laughter) Dad became Vice-President of the Clifton Forge Coca-Cola Bottling Company.
What about the development of your own personal interests, and hobbies? Did your father have hobbies, or your mother?
My father was very much interested in the outdoors, and wildlife, and plants, trees. He grieved over the loss of the chestnut trees. He did a lot of interesting things. He was interested in the native azaleas, and collected seeds of azalea bushes when they were in bloom in the spring out in the forest. And, he’d bring these seeds in and let them hibernate the appropriate period of time and then sprout. And, he had native azaleas out in the garden that he had raised from seed. Not many people get into that kind of thing, but he was into it. He had a small, what he called a “mist house.” It was a big sandbox with a heater in the bottom of it. During ice storms, ice would break off twigs of the boxwood, the English boxwood, that were around the house. My father would go out and gather these twigs, put them through a hormone solution, stick them in the moist sand. Pretty soon they’d be sprouting roots, and now I have, around our house out in the country, boxwood bushes that are enormous.
And, you’re gesturing that they’re like four or five feet high?
They are four or five feet high.
Marvelous.
And they all came from my father’s twigs.
Did he recruit you for these activities? Did you participate?
Some. Yeah. I was his handyman. (Laugh)
Ah. You were his handyman?
I could be there.
About what age would that be?
That’s a good question. The boxwood he was doing after 1955.
Oh, okay.
So I was, I was off in college. I was off in graduate school by then.
Right.
The other things, yes I would participate but it was more like cutting grass, or weeding the flowerbeds. (Laugh)
So, you took it as a chore or something like that?
Actually, I think I was more interested in doing it than he was in having me do it. I think I was pretty unskilled labor for him, (Laugh) at that point.
What about schooling? Tell us about your schooling.
Well, starting how far back? (Laugh)
Well, did you always go to a public school? Did you go to school in a regular way?
I went to public school in Clifton Forge. I think it was the same school that my father had gone to, through seventh grade. The Clifton Forge school system did not have an eighth grade, and my parents thought I needed an eighth grade. And so, they shipped me off to boarding school in Richmond, St. Christopher’s School. Richmond, Virginia. I was at St. Christopher’s for two years and they were pretty good years. I had a lot of friends already in Richmond, from summer camp activities. And so, I had friends at that school. It was not like going off to a place where you didn’t know anyone. I had lots of friends there, and they were good to me. I was a boarder. And, after two years, I came up to Alexandria to Episcopal High School and had three years at Episcopal. I graduated there.
And, this was also as a boarder?
As a boarder. Yes. And, I had my first physics course at Episcopal High School.
Did you go back home on the weekends?
No. Rarely. Maybe once a semester.
That’s really quite a bit of separation.
Yup.
Especially as a single child.
There were rare occasions when I could get home on a weekend, but it was, well, we were busy at school. There were football games and all this neat stuff.
It was a happy thing?
A happy thing. From Episcopal I went to Washington and Lee. I had no idea what I wanted to major in, but there was the, I think the family not "push" but incentive to have a business major so I could make a living. I started out as a student in their business school, but drifted more and more into the sciences. And, Washington and Lee was not a particularly good place to be an aspiring scientist. The science courses were oriented largely towards pre-med students. Relatively little pure science. The Math Department was good and I enjoyed the math and did well in it, and so I took a lot of math.
Could I take you back just a little bit?
Sure.
Back to your high school. And, you brought up your physics teacher?
Uhm-hmm.
Can you tell us if you felt this was unusual thing to encounter in high school for you? Did you have any idea what physics was?
I think I did, because back in Clifton Forge I was reading Popular Science, probably Scientific American, but maybe not. And Popular Mechanics.
I was very much into building model airplanes and trying to figure out how airplanes flew.
Okay. Where did you get your information?
From the library.
Okay.
My mother was a collector of books. We had a house full of books. I should have mentioned that her father was a Baptist minister. He was in Clifton Forge at the Clifton Forge Baptist Church on McCormick Avenue, before World War I. During World War I, he went off and was chaplain at an Army camp in Georgia, came back after the war, and then took a church in Texas, and ended up in Austin, Texas as chaplain of the, I’m going to guess it was the University Baptist Church. It was a church right down by the University of Texas. So, my mother ended up in Austin as a older teenager, entered the University of Texas and graduated in probably 1927, from the University of Texas. And, there were not all that many women, but her brothers were in school in Texas, at least one of them at the university. They all had university friends. And so, she fit into that university atmosphere very easily.
Wonderful. What was her full name, maiden name, and what major did she graduate in?
She was Bernice Green and her father was the Reverend George Green. She majored in history, I believe.
Okay. So, you said that you started out at Washington and Lee, in business, gravitated to the sciences. The sciences there, you found, were oriented toward medical, but the math was pretty strong.
The chemistry was good, too. The first year of chemistry was my favorite subject, and I liked that, and there was a very good professor there.
Do you have a name? Do you have a recollection of a name?
It’ll take me a few minutes to think of it. (Laugh)
Oh, well anytime.
We can check the old W & L catalogs. I think his name was Dr. Baxter. Hey. I just went back to my sixtieth reunion at Washington and Lee. I graduated sixty years ago. That was good fun. Not all that many of my classmates were back, but with those who were, we had a good time.
And, were they, were they curious about how you turned out? (Laugh)
Not particularly. (Laughter) We were more busy just catching up on family and things. There was one other physics major and he ended up doing radiation physics at Argonne National Lab. And so, I have seen him at other reunions and we would get together and talk physics just a little bit. But, in general, these people were not interested in science, or dark matter, or anything like that.
But you’d stayed in touch sixty years, and you go back to a reunion, I’m impressed. (Laugh) It must have been an important part of your life?
I have not been to many of the reunions. I went to my fiftieth and went to this one. Even though we were living close to Lexington, I did not go back all that often. I’ve never been back to a Virginia reunion, even though I have many friends who were undergraduate classmates.
Can you point to some point in your training when you started thinking and becoming aware of the fact that you wanted to have a career in something? You had indicated that your parents wanted you to be able to support yourself, so they directed you toward business. Was there any reaction from them when you sort of gravitated to science?
I think it was as a result of the old-boy network. I had a good friend from back at St. Christopher’s who showed up in the freshman class at Washington and Lee. We took classes together. After two years, he transferred from W & L to the University of Virginia, because he wanted to major in physics. And, I would see him a couple of times a year, see him at football games, parties, parties in Richmond, and he kept saying, “Kent, the physics over here is so much fun. You should come over and take physics here." And, I would talk to him and we would talk about what he was doing, and what he was studying, and it was a lot better than what I was doing at W & L. So, when I graduated from W & L, with a physics, physics/engineering degree…
And, that was 1953?
That was 1953. That’s correct. I decided I would apply to graduate school at Virginia, take some physics and see how it went. When I applied I guess my record wasn’t all that great and they didn’t think all that much of the W & L physics, and various things, and the person who was doing applications for the Physics Department Graduate School was a man by the name of Frank Hereford. Ten years later he was president of the University of Virginia, (Laugh) which was kind of interesting, because he was a young instructor or assistant professor when I was applying to school. Anyway, Dr. Hereford said, “Look, this is a different level of physics. You should come over here this summer, take this math course. It’s advanced calculus, advanced differential equations, series, all this stuff—first-level graduate course. And, if you get through that okay, we’ll take you in the fall.” And, I went over and had a wonderful summer in Charlottesville, and math was not all that hard, and it just went well. I did well enough in the course. So, I started in the fall of ‘53. And, Frank Hereford taught me mechanics, classical mechanics, and we went on from there.
For the record, how were you supported during these years?
I was very lucky. My parents had the resources to send me to Washington and Lee, and then start me off at Virginia. And, I’m grateful to them for that, because it was good education.
Did you work at any point?
My second year in graduate school I had a teaching assistantship. I taught a lab course in physics. I learned more than the students did. [After the summer of 1955 I had support from Carnegie.]
Right. Okay. Another thing that we should cover is that you were moving into your teens during World War II, and I’m wondering if there was any effect on you or your family? Did the war have any effect on you?
Gas rationing was an issue, living out in western portions of Virginia. There were things that we would have liked to have done and didn’t. My teeth started growing in slightly crooked, but the nearest orthodontist was down in Roanoke, and it took gas to go to Roanoke. And so, my mother told me to, “Keep pressing your tongue against your teeth and they’ll straighten out.”
Oh, boy. (Laugh)
But, it never did. (Laugh) And, I tell my dentist that those teeth in front are a little bit askew because of gas rationing.
Oh, okay. (Laughter)
There were issues with sugar shortages, but that didn’t bother us too much.
Your father was not of draft age?
No. He was older by then. He was of draft age in World War I.
They didn’t bring him back.
I’m trying to think of other things. Our family tended to go to Richmond for serious shopping; things like buying shoes for a growing boy would involve a trip to Richmond. We had to kind of space those out. But, I remember the shoe store had one of the early x-ray machines where you’d stick your feet under and you could look and the guy was fitting your shoes would look, and you’d wiggle your toes, and you could see your toes wiggle. It was terrible. (Laugh)
Yeah.
Terrible. Terrible x-ray dosages. But, it was good fun.
I remember those, too. But the question of the war, of course, certainly changed not only many lives but also a general feeling about humanity and its future. And, I was wondering, were you aware of the bomb after it happened?
Yes. I think during the war I was more involved with building model airplanes, and spotter planes, and keeping up with the aircraft. When the bomb was dropped and the news broke, I did know enough about isotopes to more or less have the concept of what was happening, and can remember trying to explain that to my parents, who were not quite up to speed on isotopes or uranium. (Laugh) I read everything I could about Oppenheimer.
Well, that certainly, gives a sense of it. Did it change your view or do you feel about what was the new world going to be like and what part you would play in it?
I think that we were sensitized to the conflict in Europe at a fairly early time. And, the reason for this was that my father’s sister married a Harvard graduate who was teaching romance languages at the University of North Carolina, Professor Wiley. In the 1930s they would spend their summers going to Europe, leading small tours of people. And, they were very much aware of the changes taking place in Europe, and would come back with stories, and I think really they were repulsed. They just could not stand the fact that Europe was girding itself for war. They were sympathetic to the issue of the Jews. They were, I think, often trying to help in whatever way they could. But they, they were aware of what was going on. They would come back by Clifton Forge and let us know about their trip, and we would hear, even as a youngster, I would hear these things.
So, you were connected?
They would come back by Clifton Forge because they left their only son in Clifton Forge while they went off to Europe for the summer. So, I grew up in the summers with my first cousin, as kind of an older brother.
And, what’s his name?
Lee Wiley. And, he ended up with a Ph.D. in chemistry and had a career with DuPont.
Now, during these years that you’ve gone to school, through the college years, there were the summers. Does that mean that you went back to Clifton Forge for the summers? What did you do during those summers?
I think in the earlier years, much of the summer was spent out on the Cowpasture River floating on the river, and swimming, and hiking, and occasionally later on there were occasions where friends from Richmond would come in and pay a visit and we’d go hiking together and do things. When we graduated from Episcopal High School, my parents threw a house party for, I guess, six guys and their dates, out on the Cowpasture River, in a log cabin. (Laugh) And, that was such a good celebration of guys and gals that everyone wanted to come back the next year. So, after our first year in college, at different colleges, we all came back and had another house party (Laugh) the next year.
That’s a lovely memory.
Yeah. It is. And, I still see some of those gals, and they talk about it still.
Well, there’s one summer, moving then along in your career, in 1955.
Wonderful summer. (Laugh)
You spent it at DTM. And, my question is, how did you get to DTM from University of Virginia?
Came to the American Physical Society meeting in April, down on Connecticut Avenue. I was in line to get a Masters, kind of wondering what to do next. I was planning to come back to Virginia and work on a PhD, but I wanted to take that summer off and do something. And, at that meeting Merle Tuve was down chatting with his old friend Jesse Beams, who was chairman of the Physics Department, and my thesis advisor. And, Beams was listening to all of this and what Tuve was saying was that he was chairman of a group that was working on one of the most important problems in astronomy, and on and on, and he needed someone who had some experience with thin metal foils. And, there was a student of Beams’ who was getting a Ph.D. and Beams tried to get the student interested in this astronomy problem, and the Ph.D. student had better sense, (Laugh) kind of kept brushing it off, and finally just said, “No.” He had another job opportunity that he was going to pursue. And so, Beams went to his number two man, who was this Masters candidate, and put me in touch: gave me Tuve’s phone number, I think, and said, “This man wants you to work for him for the summer and you should give him a call.” And, I did. Well, Tuve was just a wonderful person, but he could come on pretty strong. And, he started talking about increasing the power of telescopes, and photoelectric image recording, and how they needed self-supporting thin-metal films, and to tell you the truth I was about ninety percent convinced that this was some nut. (Laughter)
Oh, no!
How lucky can you get? Went back to Virginia and…
So, you did come up here for an interview?
Not, not quite then. I did not make contact with Tuve, except by phone at that APS meeting. I went back to Virginia, sat down with Dr. Beams and said, “Who is this fellow Tuve?” Well, (Laugh) the professor sat me there for half an hour (Laughter) telling me things that Tuve had done in seismology, and mass spectroscopy, and building Van de Graaff accelerators.
Absolutely.
He said, “Now, if any young man has a chance to work at the Department of Terrestrial Magnetism…” I think that was something that kind of turned me off too, “you should do so.”
You mean, the name of it turned you off?
Yeah. Sure.
Oh.
Doing astronomy at the Department of Terrestrial Magnetism?
You didn’t know the connection with Mount Wilson, or did astronomy not mean anything to you at that point?
Well, Mount Wilson certainly meant something. Carnegie, I think, meant something, but not Department of Terrestrial Magnetism. (Laugh) I had never heard of it, as a department.
Right.
Anyway, I said, “Yes, sir.” My thesis advisor called up DTM, told Tuve what could do, and made an appointment for me. I came up the next weekend and got hired for the summer. Now that was a wonderful summer. Summer of ‘55, was that the Alaskan Seismic Expedition?
That sounds right. Yes.
So, when I got here the parking lot out there was full of GMC pickup trucks, and vans, and things, and they were all being wired up with radios, and seismometers were being shoved into the back, and then that group kind of disappeared. Howard Tatel was involved.
Oh, yeah.
I got to know Howard Tatel. So, here I was. I had an office here, some equipment. Burke and Firor were here, John Firor and Bernie Burke. But, much of the work that I was doing, as I recall, was over at the Naval Observatory with John Hall. John had had Stewart Sharpless working on some of these image tube problems, and Stewart Sharpless wanted to be doing astronomy and not fussing around in the lab. He was glad to see me come. (Laughter) And so, I would have lunch over at the Naval Observatory. I’d drive in through the gates in the morning and the guard would give me a big smile and say, “Hello, Mr. Ford.” (Laughter) Gee, those were the days. I used to go over there on Sunday morning and play tennis on the tennis courts at the Naval Observatory. You don’t do that these days, I understand.
Now, was Bill Baum around here at that time, in that summer?
Bill Baum, of course, was in Pasadena. He spent a fair amount of time coming over here on occasion.
Now, let me think. That summer he may have been here once. I can remember going down and having dinner in the evenings. He would sort of check in and plans would be made. I don’t think he spent a whole lot of time here that summer. But, I can remember sometime in the next two years he made one or two trips by Charlottesville, and would come and see me in the Physics Department. And, there were other astronomers who would stop by in Charlottesville and see me in Physics. And, pretty soon the local astronomers started taking notice that there was a graduate student (Laugh) in physics who was attracting some interesting people coming in. And, they started being kind to me and that was very nice. That was Dr. [Alexander] Vysotsky.
He was doing what you might call “classical astronomy” type stuff?
Very much so.
Statistical things. I think he did some spectroscopy, but I don’t recall.
It was all proper motions.
Proper motions. Of course. Astrometry. And, did he take a personal interest in what you were doing?
I think he did. I think that he was proud that there was a Virginia student doing these things. I don’t think he was particularly interested in the nuts and bolts, or electronics of it, but I remember he introduced me to his graduate students and some of them later became real good friends.
Well, the question is, what were you doing? In ‘54, February, when the Carnegie Image Tube Committee was created, I haven’t gotten really to the nitty-gritty there, but it seems like there might have been a question as to how much prototyping would be done at a place like DTM, or a place like the National Bureau of Standards, of course, with Ladislaus Marton on the committee. How much and where would the prototyping be done? What would be the role of the committee itself and its relationship to academic labs like yours and commercial Labs. Had that all been worked out or was that anything you were aware of at that time?
Well it, that’s a very good probing question. I think that in ‘54, ‘55, ‘56 there was a lot of learning going on. Marton had a couple of people who got some image tubes from Fort Belvoir, and were, well I would say, “playing” around with them in the lab, seeing what they could do. And so they had a lot of hands-on experience there. But, nothing really oriented towards astronomy. And, in the end, not very much turned out to be very useful. These were electrostatic tubes.
Right. I was going to ask.
At that point.
This is stuff that was developed in World War II…
Yes.
—for night vision…
Yeah.
—and things like that? Yeah.
But they did some interesting things and that got everyone thinking about phosphorous. I think the picture was that Lallemand had started exposing the Ilford G-5 plates, these electron-sensitive plates directly to the photocathode. He had things frozen in, and to change plates you essentially destroyed the photo cathode. It’s kind of a terrible way of doing things. But, it worked to get some exposures. There was thinking that, “Maybe we can modify this to some extent so that we can still record those photoelectrons directly on a plate.” And, that’s where the thin films came in. But, along with that was the concept that, “All this money is going into the TV industry. Television pictures are getting better and better. GE has built this image orthicon with a magnesium-oxide target that has wonderful storage properties. We have to explore that.” A lot of the smart money was on TV systems. There was J. Allen Hynek, Northwestern.
I was going to ask about Cateye. Yes.
There were also Sterling Colgate’s efforts.[1] He had TV systems. There was an MIT TV system.
But this is by ‘57-‘58 already?
In TV systems, yes.
You also mentioned Lallemand. When did you first start reading about or being exposed to these concepts? Was it under Jesse Beams?
Yes. It was probably the day after I talked to Merle Tuve on the phone.
Oh, so it was after --
Yeah.
—your contact --
Yeah.
—with Tuve?
I started reading about these things. Yeah.
Had you been doing thin film work with Jesse Beams, barrier stuff?
Yes.
And, what was the purpose of that kind of research before contact with Tuve?
It was really crystal structure of the metal films. These were formed by vapor deposition, evaporation onto a cool surface. And, the grain size was somewhat dependent on the rate of evaporation. I was studying this, and what Beams was interested in, and what I was measuring, was the strength of these films. And so, the technique was to make a self-supporting film and study it as it was stressed to failure. Beams, being a centrifuge guy, had the idea that you ought to put the film on the top of a spinning top and spin the top until the film flies apart. That’s what he wanted me to do. But then, Beams had a heart attack and I was left floating as a graduate student without a thesis advisor. I decided there ought to be another way of doing this, and I had a scheme where I could put the metal film clamped on an aperture and apply air pressure very slowly with a needle valve and watch the deformation. And so, I got a thesis out of the rate of deposition and stress-strain curves. A fairly straightforward thing, but when Beams recovered from his heart attack and came back, he was obviously very pleased at this.[2] (Laugh)
Excellent.
And that summer of ‘55 I came up here and was working here. When I went back, Beams had improved on my technique. And he said, “Now, here’s the way I would like to see you do this.” And, he had a much smaller aperture that, and you formed the film right there, and then remove the backing, and it was quite clean and nice. And, that’s what I did for the PhD thesis. But, it was Beams’ tweaking of my air pressure system.
That’s a great story. Now, the purpose of going to being able to deform these mica surfaces, they were not mica at that time?
Silver and gold.
It seems to be related somehow to some of the problems that the electrostatic image intensifiers had with spherical aberration and stuff.
No. This was quite different.
Okay.
Well, first of all, is there a good record of how the Image Tube Committee got started?
Well, that’s what we want.
I don’t know. Their reports were certainly published in the Carnegie Year Books from the beginning.
I tried to go back and I got hung up. There’s one of those published things that I could not access.
It was a blank page.
Oh, okay.
It was listed in the index of the Yearbook. I need to go look at your collection of Yearbooks.
But, certainly there is a lot of manuscript material, the correspondence of the Committee, probably at P Street, at Carnegie headquarters.
Or if it’s, it was probably largely Tuve’s correspondence, which may be in the Library of Congress by now.
Could be. My understanding was that Vannevar Bush was really the motivator for that committee.
Now, the story that I heard as a young scientist here, and it was all secondhand, because I had come in a year or two late, was that Bush would make his annual visits to the departments and when he was in Pasadena he would go and talk with each of the astronomers and try and find out what they were doing. And, he got around to Bill Baum, who was doing measures of stars with a 1P21 and a pulse counting system. He was event counting with a photomultiplier. Baum made this pitch to Bush that, “The efficiency of the photocathode of this little tube is so much better than the photographic plate, there ought to be a better way of imaging this than what Lallemand is doing and something that the Carnegie Institution ought to be looking into.”
That’s very interesting.
And…
It could have been Baum.
Well, I got some of this from Bill Baum and some from others (Laugh) but Bush would nod his head sagely and then went on back to Washington. When he came around to DTM, Tuve was busy with the Würzburg dish out here in the backyard, and Burke and Firor and Helfer and Savedoff, and a bunch of astronomers here doing things. Tuve was trying to learn astronomy. And, Tuve had realized that the photomultipliers were so much more efficient than photographic plates. He had had considerable experience during the war with the industrial manufacturers of fuses that could be shot off in a weapon.
Proximity fuses?
Proximity fuses. Yes. And he thought that it was probably possible to get the imaging tube companies to build something for the astronomers that would really do a good job. And as far as I know, Tuve, not knowing about Baum’s input, hit Bush with, “This is something Carnegie ought to be doing." And, of course, the hand-waving story is that Bush was so surprised that Carnegie people on both the West Coast and the East Coast were thinking along the same lines for once (Laugh) that he decided that, yes, that was something. Paul Scherer was at P Street too, and I think Bush and Scherer talked this over, and then Bush went to the Carnegie Corporation and got a $50,000 grant. And, that got it started.
Do you feel, is there any chance, given Bush’s role in the OSRD during the war and his whole concept of the research reserve, that there must have been some interest in the military for this technology, and that clearly there was a lot going on there? That would probably be something that would have happened before you were here, or at a level that you were not aware of, but were there ever any stories? You mentioned the Fort Belvoir connection. Were there any others about the night vision, the similarities?
I cannot think of any through Bush.
Okay.
I think that both Baum and Hall were plugged into what was going on at Fort Belvoir. Hall through his interests at the Naval Observatory, and Baum had worked for Tousey and was, you know, a little bit plugged in to what was going on at the Naval Research Lab. And, I think that through those connections either Baum or Hall, or both, were familiar with this fellow who was in charge of night vision at Fort Belvoir. His name was Mike Klein.
Okay. It would be that kind of connection that they would be working somehow along parallel paths.
And then I think Klein was interested that there was someone else who might have a use for these night vision devices. So, he was receptive to lending some stuff out, and talking, and having us come down. I spent a lot of time driving from Broad Branch Road (Laugh) to Fort Belvoir in the early days. As it turned out, our detailed performance requirements were rather different. The military, mostly, at that point just wanted a soldier to be able to see something through the night vision device and recognize it as a tank, or a person, or a rabbit. Our interests were always in trying to measure something. It was either to measure the brightness or to measure the position of the spectral line. We were more interested in these long exposures that required stability of the optical system, and that was the sort of thing that really was not on the agenda for the military, or that part of the military.
Let’s go back, if we could, to the summer of ‘55 and beyond that, through to your thesis, to ‘57. One of your first activities on the barrier film problem was to evaluate it. Was this the way to go? There was a point where those design options were pretty much abandoned by ‘57. The barrier film was rejected in ‘57 as too difficult to use for a routine measurement.
Well, I’m glad you got a date on that, because I was trying to peg that. I would have put it a little later, but not, not much later.
This is partly from Louis Brown’s history.
Yes. In ‘55, I was hired to do the thin film work, and the reason for this was there was a device, designed by a committee, probably consisting of Hall, Baum, and probably Marton. It was a device where someone would make an image intensifier, electrostatically focused, photocathode, and a bottom layer. This bottom layer was made so that it could be cut away to expose the photocathode into your vacuum system. Mostly it was being done with IT&T, Farnsworth Electronics at that time, in Fort Wayne, Indiana. They would build these things. In the tube would be one of my thin films. The way that worked was that I had a bunch of Kovar metal disks that had a 1 cm aperture, or 1 1/2 cm hole in the middle. And, I would make my thin films and deposit them there, would bake these films, and the ones that survived baking for a period of time, that had no visible pinholes, would get put into a little metal casket and shipped off to Fort Wayne, and there they would be heliarced into the base of this image tube assembly. [The first tests of the barrier film tubes were done on the 26-inch refractor at the Naval Observatory in Washington.] Later the image tube and its can opener and all this stuff would end up out in Flagstaff on the 40-inch telescope at the Naval Observatory. And, there were some memorable nights working with that device. We had a dynamic pumping system in this assembly, and to keep the pumps cool we circulated water from a garbage can with a fish tank pump (Laughter) through a garden hose, up to the telescope, around, back down. And, we were working away with this thing. And, we could make exposures and we could get little images on Ilford plates. But, [Gerard de Vaucouleurs] came over from Lowell Observatory and there was deep talk about how this would be a good thing if it ever really (Laugh) was easy to work. But, in the dark, someone tripped over a hose, and knocked the return lead out of the garbage can. Pretty soon there was a half inch of water on the observing floor.
Oh, no.
And, this was in November.
Oh, no.
And, it was soon a sheet of ice. (Laugh)
Yeah. Was that de Vaucouleurs?
It was. Well, he and Baum were good friends, good acquaintances, and worked on similar problems.
This was a complex system to make work?
It was complex. First of all, you had to get a good stable film. These were aluminum films by that time.
And, this was something you were making? This was your role?
I was. I was making these. I made them. I baked them. It got so it was fairly routine to make them.
You made them here, in the lab, in a lab?
I made the first ones in the lab in Charlottesville and would send them off. And they had a test of those while I was still in graduate school. The really first successful test of the one that I remember because I was there, was in November of ‘57. I don’t know if ice on the floor had anything to do with the statement that it was too complex for astronomers to (Laugh) cope.
Gerry Kron’s electronographic instrument at Lick was very complex. It really was.
Yes. Gerry was a master at this.
He was using the barrier technique, was he not? He didn’t have to break the glass like with the Lallemand tube?
No. He had a valve. I do not remember that he had a barrier film. Our idea was that the barrier film would isolate a dirty vacuum from a clean vacuum. The more I learned about photocathodes the more it seemed that this was really not going to work at that level. But, that was the idea.
Okay. I was just wondering, would this be a good time to stop, a break, just briefly for that coffee you promised? How do you feel?
Sure.
Yeah. Just take a short break. And, then what we’ll do, when we come back, is talk about, a little bit more about your contacts in the late ‘50s with the decision to prototype at the various corporations, at RCA, Farnsworth, GE, and what your role was in that process.
And then move that then beyond the prototyping to the actual development, and your contact with McGee, Kron, Walker, all the others who were working at, on different designs, when you were a guest investigator at Lowell. Is that reasonable?
Sure. And, there were others at Lowell who were already working on this. Ted Hauck and Larry Frederick were at Lowell doing image tube things.
[Before recording resumed, Hardy showed us a newspaper story about the designation of DTN as a historical physics site. This story came about because back in Millboro Springs we had invited a friend for dinner. On the night of the dinner we were in the kitchen and the she noticed the DTM invitation from the day’s mail on our breakfast table and asked about it. We explained and forgot about it.]
But, she called up her friend who is the editor of the newspaper, and said, “You know, you really ought to get in touch with Kent Ford and find out about this.”
I’ve started recording again, but let’s keep talking about this. This is, “A Local Physicist’s Lab Recognized As Historic Site.” And, where was this published?
This was in The Recorder, which is the weekly newspaper of Highland and Bath counties, Virginia. And so, a hometown newspaper.
That’s your hometown? I will just say briefly, I am especially attached to this telescope. We have a jeweler’s model of it that was made specifically to convince the Ohio State Legislature to help underwrite it back in the ‘20s. And, it is made completely out of brass. It works.
Oh, boy.
It’s out at our Hazy Center, and I’m trying to bring it back and put it next to your spectrograph.
I have fond memories of that telescope, because, and we’ll get to this shortly, probably in ‘58 I went with an electrostatic image tube out to Ohio and worked with Sletteback and Keenan putting this electrostatic tube on one of their spectrograph cameras. The telescope was still sitting there in, in Ohio.
Delaware. Delaware, Ohio.
When I walked in and saw the telescope I was sort of taken aback, because there had been a photograph of that telescope in the physics book that I had used at Washington and Lee. (Laugh)
Oh, really?
A first-year physics class. So, yes, that telescope had been around for a while. And, now it’s grown from a 69-inch to a 72-inch.
By ‘55-‘56, you started interacting with astronomers?
Uhm-hmm.
You had already gave us the interesting view of De Vaucouleurs, that these things are awfully complicated.
Yeah. That was a little later.
Jesse Beams’ original choice for a graduate student who would help Tuve declined? You are entering what is essentially an instrument-based career. You are building instruments?
Yes.
Did you have any particular feelings about that? Were you still doing physics? Were you thinking you were doing astronomy? What were you doing, and how did you feel about it, mainly?
At Virginia I considered myself doing solid-state physics. And, I think today they might call it “material physics” or something, but it was good science. There I was really interested in the science of dislocations and crystal growth and things. Working up here, yes it was an instrument, but it was always an instrument with which you could do more and better science. I did not know that much about astronomy. I had not taken courses in astronomy. I had taken an evening course with Ned Dyer, probably in the winter of ‘57 when I was still at Virginia. But, it was a survey course. It was an interesting course. But I knew Ned Dyer was at Virginia at the time and he knew what I was doing. And so, I was a little bit of a ringer there. But anyway, I learned a little bit of astronomy. In ‘57-‘58 there was just a lot going on. Baum was out in Pasadena working with a young man on television systems, various sorts of TV tubes. I was here. At one point we took an electrostatic tube, I believe, to Mount Wilson and worked with Olin Wilson. He was interested in the structure of H & K lines, calcium lines. That was a small field project. There was a camera that we could adapt to fairly readily. And so, my recollection is that the only real astronomy that was being done then, and I may have the time a little bit confused, was taking a tube to Mount Wilson and working with Olin Wilson. Now, the spectrograph of the 100-inch was sort of a sacred instrument. You couldn’t just go and drill holes in it to match your image tube to. (Laugh) You had to be a little more sophisticated than that. But, the electrostatic tube, I think I’m remembering the correct tube, is the one we could fit into the space of an existing long-focus camera, and that worked fine. And then we would compare that, those results with Olin Wilson’s direct plates on a shorter focal length, a 32-inch camera, and made our comparison that way. And, we got a little paper in PASP out of that.[3]
But, at this time, you were comparing your aided, and what was called at that time “aided and unaided photography” --
Yes.
—to see what kind of gains you could get and what kind of problems you could tolerate to get those gains? I think that was the balance, the practicality balance. You had three types of image tubes you were working with, barrier membrane, cascade, and a simple converter with a mica-window output.
Okay.
Using primarily the 40-inch at the U.S. Naval Observatory, Flagstaff, and the 24-inch Lowell refractor. And, this is when Hauck and Frederick were with you. And, you found, by ‘59, and this is the Report of the Image Tube Committee of 1959.
Okay.
And, it actually came out as a Lowell Observatory bulletin, which I thought was kind of interesting, or they repeated it or something. The barrier membrane was only ‘slightly better’ than direct photography, whereas the other two provided 30x increase in sensitivity. But, as you just pointed out to me, the barrier membrane was one that you could fit into a sacrosanct spectrograph without altering it. But, the others, if I understood it right, took much more room.
I think it was the cascaded, the electrostatic cascade tube that could fit in, not the barrier film.
I see. Well, I’m trying to get a sense for the importance of helping astronomers, providing a tool to astronomers that was much better, but was not so much a change of the way they do science. How aware were you of that tension at the time?
I was pretty aware of it, because I knew that my specialty was making those thin films. That’s why I had been hired. (Laugh) But, I was doing other things too, and I very soon was involved with building the camera assembly for an electrostatic tube. That was to be tested at the Naval Observatory 40-inch. By that time, John Hall had moved from the Naval Observatory here in D.C. out to Flagstaff to become director at Lowell. And, maybe you’ve got a date on that. Fifty-eight, fifty—it’s somewhere in there. The result of that was that Hall had been the person who was really maintaining contact with Farnsworth, ITT, RCA, Dumont. And, when he left D.C., Tuve gave me that responsibility. And, part of that scene was that the AEC had an image tube project, and I got involved with attending the AEC meetings for developing image tubes. We were all looking at sort of the same things and we would compare notes on where we were going to spend our money. There was a little bit of logrolling going on back and forth to try as many ideas as we could there. But, there were some very good people in the AEC group. George Reynolds from Princeton, Marty (laugh) later won a Nobel Prize. Perl. Marty Perl. And, they were good people and they were interesting meetings, often held in connection with APS meetings in New York and elsewhere.
And, this was for large-area detectors for accelerators?
It was for recording transient events.
Transient events?
Yes. In solid scintillators, largely, fiber optic scintillators, and various things. They had a light-gathering power problem, and were looking to the image tubes to solve some of that. I think we benefited from the money that the AEC put into image tubes, a lot more than the AEC group benefited from what Carnegie put in.
Because I know Carnegie, yeah, put in the initial seed funds and then it was NSF after that?
That’s correct. But I was saying Carnegie funds, including the NSF contribution.
Sure. Okay. But then, in effect, you benefited from AEC funding as well, the product of it.
Could we talk about the funding angle for a moment, Kent? I mean, it’s always been my understanding that the institution had, up until that point, been very loath to accept any external funding for anything. So, was that initial funding from the Carnegie Corporation a first?
At the time it was my impression that our NSF grant was the first for Carnegie. Later, let’s see, who was the president of Carnegie who followed Bush?
Haskins?
Haskins sort of corrected me on that, but he never quite had the figures to back himself up. I don’t know. I thought it was the first, and it was the idea that the money would be spent at these industrial labs, and to a large extent that certainly was the case. I mean, none of my salary, either as a summer student or a graduate student, or moonlighting for Carnegie, or any of that was ever paid with NSF funds. When we got the first NSF grant, it was to develop the C-33011. This is probably the better one to photograph.
Are they the same?
Yeah. These are the same.
[Following passage set has accompanying video clip, to access please contact nbl [at] aip.org]
NSF funding started when? Because, I know that we were involved during the IGY, the big seismic expedition that Tatel was involved with, and a lot of other people from DTM. I had heard that this was the first major NSF funded DTM project, but I wonder if it’s contemporaneous with image tube funding?
Well, I would have to go look at a Year Book. It was about the same time. I expect the IGY was the first, because I don’t think we went after NSF money until ‘58 or later. Was the IGY funding, was that the Peru Expedition in South America?
Right. The Andes.
David Tatel was a student. There’s a Judge David Tatel of the Appeals Court of D.C. who is now a distinguished Judge.
He was a teenager on there, assisting his father on the expedition.
He was out here for the celebration of this plaque.
Yes, he was. Takes a strong personal interest, still.
[Following passage set has accompanying video clip, to access please contact nbl [at] aip.org]
Please describe these two instruments in front here.
Okay. These tubes were made by RCA. RCA had model designations and I believe they called these the C33011s. I’ll have to check that. This is what the tube looks like before it’s encapsulated in the high-voltage insulation.[4] Silicon rubber.
What are we actually looking at? Is this white circle the cathode?
No. This is a dead tube. So, the cathode doesn’t have much color to it. This one presumably still has some life, and you can see a better reflection. It’s not just the glass.
They kind of look alike in the camera. (Laugh) That’s the trouble.
Well, you’re looking inside from the one that still has a cathode. You do not see the interior elements.
But, this one you can easily --
—see the interior?
Yes. And so, this one has gone to air, someplace for some reason. (Tapping)
That means there’s a leak in it?
There’s a leak.
Now, what are we looking at here, this structure, these rings?
Okay. Let me point out, first of all, that there’s symmetry here. This is the first half. This is the second half. This is where the electron multiplication takes place.
So, there’s a membrane there?
There’s a membrane there. The scenario is that photoelectrons from the photocathode are emitted. These are accelerating rings, very much like Tuve designed for the Van de Graaff years and years ago. These are accelerating rings that take the photoelectrons through a potential of 10 kilovolts. They impinge on a phosphor screen here, on one side, in this interior. One side of a supporting window, and there’s a second photocathode on the other side. So, you get secondary photoelectrons, if you wish, coming off the second portion. They are accelerated through another ten kilovolts and (Tap) hit the phosphor screen.
And, that’s where you put the photographic plate?
That’s where you put your camera to photograph that screen.
So, that screen becomes the image? Or, the object --
Of the camera. Yes.
And what is the silicon—this is a silicon rubber ring?
Well, we generally ran the photocathodes at ground potential, the phosphor screen, at twenty kilovolts. At twenty kilovolts, at observatory altitudes, like Flagstaff, it’s easy to get corona sparking. So, these structures were painted with a non-conducting black dye, and then potted with the rubber and that stabilized the leads that were soldered onto the corona. All these rings are Kovar disks, Kovar having a property, a coefficient of expansion similar to that of the glass.
Are these the same as are in the instrument that we have on display, the spectrograph that you and Vera Rubin used for the radial velocities of M31?
These are the first versions of the tube that appears in your instrument. The instrument probably has a later model tube that, instead of having a glass envelope, has a ceramic envelope. It will operate at a higher voltage. We would run those at thirty kilovolts. And, you can tell the difference, because these tubes have nine leads and the ones that, on the later models have twelve leads. The tube is just slightly longer. They have one more set of accelerating electrodes.
Do they have one more set of the…
No.
So it’s one acceleration? I mean, one re-imaging in the middle?
Right.
But, more of the accelerating?
That is correct.
Rings? Okay.
Now, they did make a three-stage version. Roger Lynds used the three-stage version at Kitt Peak quite a while. That had its own characteristics, advantages, and disadvantages.
I recall the spectra that he would produce were nonlinear?
They were broad, but they were also curved. It might have been with the magnetic field he had. I’m not sure what it was. But, he used those tubes to great advantage, because he was looking for very faint features. And the trick was to actually move the photographic plate while you were making your exposure. So that you would get a widened spectrum. And, these very faint lines would show up just as an occasion scintillation in that three-stage tube, but it would make an impact that you could recognize as, “Hey, there’s something there.”
So the two tubes that Louis Brown recalls that characterized the two stages of the development of the Carnegie tube, was the C70056 and the C33011. I take it this is, then, the C33011, what you just showed us?
That is correct. And the 56, my recollection was that was the earlier, infrared version of the same tube.
Okay. It says, “By 1963, RCA had fabricated more than a hundred of the C70056 cascades, continually making modifications. And the No. 107 finally met the demands of the committee.” So, maybe that was never really distributed like the 33011.
You’re probably right.
Well, no, and that’s Louis saying that.
Yeah.
Okay. Do you have or are there here on the table examples of that developmental one, the C70056?
I will have to go back and read through the notes to figure out what that was.
[The RCA C70056 was the first magnetically focused tube that we worked with. This was basically the tube that had been developed for Fort Belvoir: it had the green P20 phosphor screen. The C70056-E was the infra-red version with the S-1 photocathode. For astronomers, RCA tweeked the production to blue output phosphor (P11) and probably s-20 multi-alkali photocathodes. Later RCA designated these tubes C33011s. They were to have low background for long exposures and fine-grained, blue phosphors. Much later, the ceramic tubes were the C33063s.]
Okay.
Kent, on the topic of what’s here on the table, can you tell me what is this? (Laugh)
Okay. Now, you’re pointing to?
A big image tube.
A big image tube.
[Following passage set has accompanying video clip, to access please contact nbl [at] aip.org]
Well, they’re huge.
When these cascaded tubes became developed to the extent that we were actually using them and doing some astronomy, and others started taking notice, there was interest in an even larger image area, and I think this was largely an Air Force reconnaissance effort. They wanted to be able to take photographs of the ground as it was moving by, taking snapshots quickly. And, so some government agency, I believe it was the Air Force, it could have been Fort Belvoir, it could have been both, had RCA build what was called an 80mm version. These were called 40mm versions.
These are the forties?
Forty millimeters was the size of the cathode phosphor. And, this was twice the diameter.
And these bumps here are the accelerators?
Yes.
Okay.
You can see.
As far as we can tell. But, it operates on the same principle?
Same principle.
And, that’s the screen.
We probably had a resistor string built in for the dividing the voltage among the accelerators. Only three leads coming out? I had forgotten about that. Anyway, we, we, what did we do with these things? We had a couple of them. We used them to try to make some sky photographs. It was a little bit of a side effort. It was just not our main focus of activity. One problem was, we were still dependent upon a camera to reimage this thing. It turned out getting high-quality camera to image 80mm diameter field with reasonable optical efficiency was not easy.
That’s bigger than a Hasselblad?
Yeah. And so, it was getting unwieldy in size.
What are the approximate year ranges for these different instruments? Start with the thirty-three here.
Well, I remember the 33011s as being the first magnetically focused image tube that really came along and could do anything. That would have been in, what, the late ‘60s maybe?
Looking at the, the chronology that I developed from Louis Brown’s article, 1961-62 he calls the “years of decision,” as to what design to go with. And, that was when the cascaded image tube was chosen over the others. Then, in ‘63 RCA had fabricated more than 100 of these C70056 tubes, and only by No. 107 “met the demands of the committee.” And then by ‘64 the committee decided to use the RCA cascaded 33011s for distribution to observatories. So, Brown states that it seemed to be that—and I’m not quoting here. I’m sort of inferring that by the time the 33011 was produced the development had reached a plateau. You hoped for improvements, but at this point said, “Oh, it’s now time to test them in the real world.”
Okay. There’s one piece missing in here, and that’s in the period of ‘57-‘58. Ted Hauck and Larry Frederick were at Lowell, I think with Carnegie money or half of their salaries were Carnegie, or some such thing. And, they were working with electrostatic tubes. Larry Frederick was interested in double stars. These electrostatic tubes had small fields of good focus. But, he was taking movies with them, and trying to catch the seeing conditions, the turbulence in the atmosphere at times when you’d get a good sharp image. He would have reels, and reels, and reels of movie film that he would scan through looking for the good images. Ted Hauck was a wonderful guy, with a good experimental technique. He was playing around with the infrared tubes. He had some scheme of cooling them with dry ice, and he was taking the little electrostatic night vision devices and rigging them up with his camera, and Tri-X film, or something, and taking infrared spectra. And, gee, I forget how he got those. But, he had some little breadboard thing that he put on a telescope and was getting spectra. It was that work, I think largely by Hauck and maybe Ken Hallem, who was at Lowell. Hallem ended up Goddard. He showed that the cascaded tube really could be worked, and they had real promise. What was needed was the larger field than the electrostatic tubes could provide. And, the larger field was this magnetically focused device.
You’re pointing to the 33011?
Either one of those 33011s. The military was less interested in these because they were too heavy, and bulky, and took magnets and things.
Oh, you mean for field use?
For field use. Commanders, tank commanders, and the battle stations could use them with big supporting optics to see things. But [this was] not what the military at Fort Belvoir was really looking for. So, at that point, Carnegie’s money, and ITT and RCA, made a big difference.
So, what was this year of decision? This is what you just pretty much described?
I might have to read through some of the old Year Books, but it was in the period of ‘57-‘58. It’s probably ‘58. I have various markers there. Fifty-seven was when I joined DTM as a staff member. September ‘58 was when my wife died, leaving me with a little boy. And, I remember trips, making arrangements for someone to keep the boy while I was in Ohio, or Flagstaff, or something. We had plenty of support.
Yes. But that’s a traumatic thing to happen. We haven’t asked you about your marriage.
It seems to me that the decision that we were talking about was done probably in ‘58 or ‘59. It was done in the director’s office at Lowell Observatory. I remember being a little bit disappointed that there was not more support for the barrier film work, but I agreed with the decision that these cascaded things that gave you an image looked pretty good.
Did you feel threatened? I mean, that was your specialty.
I was, yeah, I felt threatened because that’s really, I like these thin films. I had spent a long time studying them, and that was what I was fond of. And, “threatened” is not the right word. I was well plugged in to DTM by then.
That’s an important thing to feel that you’re working at a place where you are secure and you are appreciated?
Yes.
Let me just, though, ask for clarity from a novice standpoint. There are certainly thin films in the cascaded tube.
Yes.
Now, did they, were they a different technology or a different craft than yours?
Yes. The industrial outfits had a way of cleaving mica into very thin sheets. At this point I’ve forgotten whether they did that cleaving themselves or were able to subcontract it out, or (Laugh) get some purveyor to furnish them sheets, I don’t know. I had to be careful when I worked with the industrial people, because they did not want some of their technology to go from one lab to another, one plant to another.
No kidding? (Laugh)
Yeah.
Talk about classification.
Right. And, I tried to be very discreet about that. There were some things that I did not probe too deeply on. But that, surprisingly, was never a real problem. When we started pushing for better resolution they were able to come out with thinner mica window support systems. But, how they did it, I was not privileged in.
But, what is the relationship between the thickness of the mica and resolution?
The scintillations from the primary photoelectrons take place in a thin phosphor layer, which is back aluminized. So that light does not feed back to the photocathode. The light from the scintillations is distributed with a Lambertan shape, a big cosine shape. The closer you get to that, the better your resolution will be. So, the second photocathode you want very close to where the scintillation is taking place.
Thanks for clarifying that. You mentioned your wife and your child. And, of course, this is a very important part of your life, and we would like to record, if it’s okay with you? How did you meet your wife, who was she, and what happened?
Fateful summer of 1955. I was in Washington. I was living at 5142 Broad Branch Road, one block that way. Upstairs room, private home. I had a few friends in the Washington area, but not very many. I had a lot of friends in Richmond, but not many in D.C. I started going out hiking with the Appalachian Trail Club, the Potomac Appalachian Trail Club. And, that was kind of fine because there was a fellow down at the Geophysical Lab who was very active in the Appalachian Trail Club, maybe one of the founders, but I forget his name. (Laugh) Anyway, on one weekend a small group of us went out hiking and there was an attractive gal about my age in the group, I guess with someone else. I’m not sure. (Laugh) She was a secretary to the executive director of the Association of Land Grant Colleges and State Universities. Had an office down on Mass Avenue, near P Street actually. But, we got to be friends and we had similar interests in the outdoors, and I went home with her phone number. (Laugh)
That’s great.
So we hit it off that summer. Spent the rest of the summer doing things around D.C. together, going to concerts over on Georgia Avenue. That’s the park over there. George Shearing played over there.
On Georgia, on the edge of Rock Creek Park?
Yeah. A lot of fun, low-cost things that we were able to do. I went back to Charlottesville. She stayed here. But, pretty soon she was coming down to Charlottesville on the train for weekends, and we were married within a year, I guess, a year later.
What was her full maiden name?
That was Emily Katherine Russell. When I met her, I remembered her name, because it was the same as the fiscal officer at DTM, Miss Russell. (Laugh) And, later on we got to talking and she asked where I worked, and I said, “Oh, a place you’ve never heard of, the Department of Terrestrial Magnetism. She said, “Oh, do you know Helen Russell?” (Laugh) Helen was her aunt, sister to Dr. Russell, Emily’s father.
So, you were married? You had a child? What happened to your wife?
She died from an asthma attack, essentially.
Oh, my.
She had hay fever. She had been treated for it. We were careful with dust and ragweed, and all that sort of thing.
Boy.
We came back from Charlottesville to D.C. in ‘57, rented a house for a year at 7300 Summit Avenue, Chevy Chase. After renting for a year, we had been watching a house that had been on the market and hadn’t sold at 7400 Summit Avenue, and we bought that house. And, Emily died six weeks later.
Oh, my heavens.
Never knew, really, what had triggered it. She was very healthy, hiked, played golf.
Oh, my.
Yes. And, in the meantime we had produced William Kent Ford III. (Laugh)
Okay.
And, I think my greatest regret is that Emily didn’t get to see Kent grow up. Because, he’s a great boy. (Laugh)
What’s he doing now?
He has made a career as a professional athlete. He got interested in canoeing here in D.C. on the Potomac River and did slalom canoeing on the U.S. Canoe Team for years, was once the U.S. slalom champion, paddled with Bobby Robertson and the Lugbills. They were world champions and did things. He got into coaching. What he’s done is he’s made a living by making instructional videos. He’s had contracts with the Red Cross, the Coast Guard, various places, for safety-oriented films. Now if you buy a kayak at the local sports goods shop you can buy a video [with him] that shows you how to paddle it, how to roll it.
I think that’s who came up when I Googled you. (Laughter)
Could well be. He has a small company called “Performance Video.”
Oh, okay.
He and another buddy of his have had a business of announcing slalom races and he has announced something like the last four or five Olympic venues for the slalom racing.
Great. Wow.
So, he’s been all over the world and working with all these organizing companies. He’s taken young paddlers to Europe to paddle in the European circuit. If you think taking image tubes to Flagstaff and Tucson is hard, try taking kayaks and canoes to Europe. (Laughter)
Well, we’re going to get to your experiences that way.
Okay.
Let’s go back to the decision period.
Okay.
What did it mean to be a staff member at the Department of Terrestrial Magnetism, a department that nobody can figure out what it means (Laugh). Was it called a “department” because that’s what you had in Washington, as far as you were concerned?
It had been a department.
Forever?
From before I was born. So, I think it was just organizational.
It had a very ponderous name. Initially it was the Department of International Research in Terrestrial Magnetism. And, somewhere within the first year or two, that got truncated to DTM.
I had not heard that. We used to have a photograph of Carnegie hanging right up there, and it was inscribed, “To the Department of Terrestrial Magnetism, (Hardy: Right.) whose job is to make the seas safe for navigation and to correct the mistakes of others.”
Yes. Yes.
And we all laughed about that.
And we still have that.
That’s great.
We moved it. (Laugh)
And, it used to hang right up there.
But you transitioned from, you know, within the space [of] a few years, going from a summer student, who had never even heard of Carnegie, to joining the staff. Did you jump at that opportunity? Did you have to think about it? What was your long-term thinking at that time?
I had enjoyed the summer very much. The work had gone well. I was spending most of my time at the Naval Observatory, but I was over here some and I had the equipment here, equipment that I was able to take back to Virginia. John Firor was very supportive.
Yes. Firor. Okay.
He became director at HAO. Bernie Burke was working with Tuve. There was just a lot going on. It was a great place to work. And, I was able to continue that association a while, for the next two years, in Charlottesville. Because, I was making these thin films and shipping them off, and John Hall was arranging for some of the stuff that I needed to have on hand, to be made in the Naval Observatory shop. So, there was stuff back and forth. I would come up and visit. I’d stay with John Hall and his wife. So, I kept an association with DTM. As the PhD graduation approached, I had a number of opportunities to go for interviews and none of them really struck me as being as exciting as coming back to DTM. One was at Westinghouse, because we had had some image tube dealings with Westinghouse. I think the guys that I worked with on image tubes at Westinghouse kind of wanted to hire me. Westinghouse’s management was looking for people to work with their atomic power and nuclear power systems. I interviewed both places. I remember going to the Westinghouse atomic pile and talking about what was going on there. And, they said, “Well, we have certain days when we run this and certain days when we don’t.” I thought that was kind of interesting and I asked, “What days do you run it?” And, they said, “On days when we’re sure that there’s no inversion layer. So, if something goes wrong it won’t all settle down right here.” (Laugh)
Oh, my god.
And, I decided I did not want to get into that business. (Laughter) Cloudy nights were one thing, but waiting for days when there was no inversion layer so you could do an experiment with your pile was too much.
That’s a bit scary.
There were a few other opportunities, but that was one that I certainly remember. Anyway, I wrote a letter to Tuve and asked for a job, and Tuve was off in South America. And I’m not real clear on the timing of this, because I think this South American seismic trip was that summer of ‘57. Tuve must have gone down to scout out the situation and make contact with some seismologists or something. Anyway, I didn’t hear anything back for, it seemed like forever. For weeks, and weeks, and weeks there was no reply from the DTM. And, finally I did get a call from Tuve and he was enthusiastic. He thought I should take the next year and go off and do astronomy at a university someplace. Well, I had had it up to here with schoolwork by then and I wanted a real job and was not interested in going to Wisconsin. Tuve wanted me to go to Wisconsin and work with Art Code and various people.
That would have made very good sense. Yeah.
That would have been a good thing for my career as an astronomer. Tuve had a warm personality. He was interested in his people and he could see that I would be working on this project, but that I had no astronomy and that I should get some. And, he was right, but I didn’t do it that way. (Laugh) Eventually he hired me as a staff member, which was quite remarkable, and I think he made his pitch that I had worked for two, two and a half years for the project, and they knew me, and knew what I could do, and knew what I couldn’t do, and they wanted to hire me and that was that.
You are listed as a Carnegie predoctoral and postdoctoral fellow from ‘55 to ‘57. What is the reality of that?
I don’t know. I considered myself a predoc when I was here. When I was at Charlottesville, I think I considered myself on a Carnegie fellowship. Carnegie paid me the magnificent sum of some hundreds of dollars per month. (Laugh) And, that was great.
So, that’s worth checking officially, but you certainly were supported by the Carnegie during your graduate years.
I was supported, and I suspect that that was coming out of the original $50,000 grant too. But, I was providing a service. I was providing the thin films.
Well, were you here again in the summer of ‘56, or you were at Virginia that whole time them until you came back in ‘57.
Good question. I think I was only here for that summer of ‘55. I think that in ‘56 I was up here at the Naval Observatory. I certainly would check in over here. I don’t think I had any work going on in this building here, in the other building. I think I was just a visitor up here at that point, but I was on a Carnegie fellowship year-round, (Laugh) as far as I could tell.
But, other than Tuve—Tuve’s involvement, you were not actually working directly with anyone else at DTM, is that correct?
Except the shop.
The shop? Who was running the shop?
Scott Steiner was running the shop. Jack Lorz was the instrument maker.
Bill, wasn’t it, William?
Bill Steiner. Lorz was the instrument maker. Steiner was a German who had been here since the early days making nonmagnetic instruments for stuff.
You possessed what one might call a unique craft ability to build these barrier membranes. (Ford: Laugh) Were you here to continue to do that, partly, and did you find that you had to impart your craft knowledge to others? Was there ever any pressure to do that?
I was never under any pressure from Tuve or anyone else to get anyone else involved with the technique. Tuve wanted to make sure that I had published the techniques that I was using, and I had, and I told him where it was published. As far as the transition, that came pretty easy because very soon I was saying, “Well, RCA is going to send down an electrostatic tube and you should mount it up and get it running for us.” And, I did that with the shop people downstairs, but that was after I came here in the fall of ‘57.
There was some issue as to what I should do in the summer of ‘57. And, part of the issue there with me was that our son had been born on graduation day, my graduation day, (Laugh) the 10th of June in 1957. And, I had a little bit of work just to finish up cleaning out the lab in Virginia, and I wanted most of that summer to be with my wife and baby boy, and take her back up to Rome, New York where she had grown up, and show off the boy. So, I essentially took that summer off. I think I wrote Tuve a letter that I was so excited about being a new father I did not want to handle the delicate thin films for a while. (Laugh) He took that good naturedly.
But that was definitely regarded as something that not anybody could do. And so, what was it about you that brought you to that level of expertise?
Well, you see, others had been working at it. I think Stewart Sharpless had had a go at this. And he was not really interested in crystal structure and strength of thin films and things. Was there anyone else? I don’t think it was ever—they had good people who did this kind of work at the Bureau of Standards, but they were not part of Marton’s bailiwick. So, there was no pressure to teach someone else how to do it. I don’t think they considered me indispensable. It was just that I could do the job and they didn’t know anyone else around who would do it.
In coming up with what is essentially a new technology, making it practical for either scientific use or commercial use, did you ever envision that you were going to be in your lab building these things for the rest of your life for every astronomer on the globe?
Uhm… (Laugh)
You probably wanted somebody else to do it, (Laugh) or did you?
No. I don’t know. That may have been a fond hope. I’m not sure. (Laughter) It just was not an issue. I was happy to be doing what I was doing.
Okay.
Gee, I should have brought some of those things. I still have the little caskets that we used to put the Kovar rings in for shipment. The little casket would then be supported by springs in a box so that they could be shipped parcel post or something.
That would be wonderful to have. It would show how delicate they are. It would help, at least, you know, if we are ever to show where this technology came from, or to help future people appreciate just what the challenges were.
Coming back to this decision making, I do remember a feeling of some disappointment. “Well, all this thin film work hasn’t really panned out to produce a working instrument.” Even though we made exposures, we’d done things—that was all right. I got busy building the next thing. And, it was built here in the shop. We took it out to Flagstaff.
The next thing?
This was the electrostatic cascaded tube. Well, this was an RCA tube. And, my guess is that it was this 056, but I just, that’s a number that has slipped my mind.
—but this is the instrument from the Tuve article of ‘58.
Okay.
It’s an RCA cascaded tube.
[Following passage set has accompanying video clip, to access please contact nbl [at] aip.org]
Yeah. Okay. I can tell a lot about this,[5] because this was a thing that I built, or had built in the DTM shop. This is the voltage divider for the accelerating electrodes of the electrostatic tube. There’s a transfer lens in here and I had learned about transfer lens through my association with these AEC people. And, there was a place in Chicago that would take camera lenses and mount them front to front to make a one-to-one reimaging system, and we would get those things.
Is this a sample of the tube itself?
That is the tube. This is the phosphor and cathode ends down.
Okay.
My big shortcoming in this was that I had not allowed a mechanism up here for focusing the transfer lens. It was an optics problem. There was a photo, there was a phosphor screen here. There was a photographic plate there. That distance was determined by the optics that we were using. We had set it up, had a place for the plate holder, and I just did not put a focusing mechanism in there. (Laugh) Well, we got out to Flagstaff and Baum looked at this and said, (Laugh) “How do you focus?”
Oh, yes.
And, you know, that was something I had just not appreciated at the time. (Laugh) Well, this was the first time I had ever worked with the cascaded tubes.
Maybe, see this was Tuve’s advice to you, to live with the astronomers for a while, maybe. Oh, that’s marvelous. That’s just wonderful.
So, Baum and I designed a system right here, which consisted of two wedges that would slide over each other, driven by a screw, and that would move the plate holder in and out, and you could get a focus that way. The Flagstaff station had a good shop, and an instrument maker, and his name was Joe. Art Hoag was running the station. Joe Eagan had grown up in this neighborhood up by the Lafayette school. Good, good man. A good instrument maker. And he had built this in the shop right there.
The focusing mechanism?
The focusing mechanism.
Great. Any idea where this instrument could be today? (Laugh)
Possibly at an attic at Lowell Observatory. (Laughter)
It’s possible it came back here, but I doubt it. I think it stayed in Flagstaff. Because, you see, that was just at the time that Hall was moving out there.
Yeah. And that would have been the Naval Observatory station there?
Yes. I think that was in ‘58. There was a big aurora.
Yes. It is ‘58.
There was an aurora out there that year, and we were all out in the Flagstaff station with cameras, watching the big red aurora come over the San Francisco Peaks.
But what struck me about this caption was it says, “The only auxiliary equipment required is a commercially-available power supply.” And then at the end it says, “The complete mounting weighs fifteen pounds.”
Yes.
Sounded like an advertisement to me. (Laughter)
Yup. Where was that published? Was that a Year Book?
Tuve et al. 1958 ["Results of Preliminary Tests of Cascaded Image Converters," Tuve, M. A.; Ford, W. K., Jr.; Hall, J. S.; Baum, W. A. Publications of the Astronomical Society of the Pacific, Vol. 70, No. 417, p.592.]
I wonder if that’s not an IAU report then?
Could have been. Could have been. The photo reproduction wasn’t too good. While we’re talking about some of this stuff around here, I notice that there is a label that left one of these instruments? [image may be available in Niels Bohr Library & Archives]
Right. I was hoping Kent could tack that up.
Oh, so that was already separated?
It was separated in the drawer.
Oh, too bad, because that is the old fifty-seven label.
056.
It didn’t just fall off now. It was separated when I opened the drawer this morning.
I think that is the label for an infrared tube. And I’m not sure if I could tell a infrared photocathode from a hand-made one. These were multi-alkali photocathodes. It’s on the outside on this one?
My guess is that the 056E was an infrared tube, but without going through all the image tube reports…
Okay. For the purpose of the interview then, let’s just leave this as an open question.
Yes. Open question. [break]
I think when Tuve hired me it was clear that I was to work on the image tube project. I think that many of the hires were a little broader than that and there was some choice as to whether you did radio astronomy, or worked with the Van de Graaff. It was not much, but there were some hires who probably felt that they could choose their science to do. And, I was told that I was to work with the image tube project, and that was fine. That’s what I wanted to do. I was going to do science with the image tube project and Tuve wanted that. He wanted me to do astronomy with this tube. And, I think part of the reason for hiring Vera was that Vera was a real astronomer who did better astronomy than this guy Ford was doing. (Laugh)
But, it was to put you two together?
Yes.
Louis Brown says basically that. Before Vera came you were assisted by Alois…
Alois Purgathofer, an astronomer on leave from the Vienna Observatory
He assisted you in the early installation and returned from time to time to help design the system for the infrared tube that RCA supplied.
Uhm-hmm.
Okay. So, that was an infrared tube. And, then Vera came as a staff associate in April 1965. And, in a way, the way Louis describes it, you might want to finesse this or change it, he says, “That’s when astronomy actually began here at DTM. There really was no astronomy before then, no one doing astronomy.”
Well, optical astronomy. Right.
Yes. Optical.
That’s a fair enough statement. It’s not completely accurate in that, well, I’m thinking of Olin Wilson, and Baum, and Firor, and various things.
On the West Coast? Yeah. But it was really the East Coast?
Yeah. That was the equipment that had been built here and taken to Mount Wilson. But, you know, I think Lou had it right there. What I remember about Vera’s coming, is that Bernie Burke had the corner office on the floor below us over there, which is now the director’s office. I had the floor down here, the office down here, on the floor below. John Firor was in between. And, Vera was told that she could have a desk in both Bernie’s office and in my office. And, Vera came in, walked down from her house to here, and looked around, and spent a little time with both of us. But, I had a spectrograph in my office that I was putting together, ready to take out to Flagstaff. And, I guess Bernie had a lot of records from the telescope out in Derwood, Maryland. But, Vera ended up working in my office. She moved her stuff into the desk there and we shared an office for a long, long time. First on this first floor, and then on the ground floor of this building.
So, there is a question whether she would have worked on radio astronomy with Bernie Burke or in optical astronomy with you?
She was hired to come to DTM as a staff member and she could choose her science.
Do what she wanted?
Yeah.
So, she chose the optical?
Yes.
Did you meet her after it was a fait accompli, or did Tuve talk to you about her?
No. I had known Vera. We had all known Vera. Georgetown ran a colloquium series and trying to learn some astronomy I would always go to those Friday night colloquium series, and I had gotten to know Vera then. She would sometimes give a report. She had been to an IAU meeting or a symposium and gave a report on galaxy structure or something. She had spent time over here as a visitor talking with Bernie Burke and others about 21-cm work, galactic structure. I think she probably was helping Burke and Tuve get their act together as to what they would be doing with the telescope. The big advantage of that telescope—which Lou may or may not have covered entirely—was that they had built a fifty or fifty-six-channel spectrum analyzer for the 21-cm line. That was a big Rube Goldberg thing (Laugh) Everett Ecklund put together, but it worked. And, Tuve had the good sense to have them build it, or rebuild it, in a trailer so they could take the trailer to Green Bank. Did lots of things that way. Anyway, Vera and I soon ended up going out to Flagstaff to do work on the 69-inch, and they were the QSO days, the quasar days.
As Louis says, there was a point when you became a world traveler. And, that is to carry the systems, the RCA system, plus the vital support system that you built here, to various observatories and then you would train them, the astronomers, in how to use it. And, he said that by the time you left each observatory, they knew how to use these things. I would be very interested in recording any particularly revealing experiences you had at different observatories, getting different astronomers to feel comfortable with this new technology. I know the first place you went was Yerkes.
Okay.
And, I assume that was Hiltner, or somebody?
[Following passage set has accompanying video clip, to access please contact nbl [at] aip.org]
I was actually thinking earlier than that, when I went out to Delaware, Ohio to the 69-inch. We went out there with stuff. I guess it was the electrostatic tube. I’m sure it was the electrostatic tube. At some point, had to hook it up, and the leads were kind of like this, but they were not soldered. They were not tinned for some reason. And, I asked whoever was standing around, it could have been Keenan, could have been Slettebach, if I could borrow a soldering gun and tin these leads. And, Keenan said, “Well, we don’t have one here, but I think there may be one over in the physics department.” (Laughter) Well, you know, this was my first visit to a big observatory. (Laugh) It was big. And, not having a soldering gun was something that was pretty amazing. I’d had a soldering gun in my toolkit since I was, (Laugh) oh gee, fourteen years old. So there was a little bit of business about electronics there. As far as the image tubes, I think they were all pretty eager to give it a try. They may have had some skepticism, but they didn’t let it show. I think that in the case of someone like Hiltner, he probably thought that he had a better scheme that he could maybe learn from what I had and then make something better.
Was he your primary contact at Yerkes? Did you work with him closest?
Probably so.
Go into the notes to see with whom I was working. And, what I can remember about Yerkes is that I spent time out at Williams Bay Wisconsin, and that was mostly with Charles Cowley. But, that was later on. It must have been Hiltner. Hiltner and I became good friends, and I would often visit him and have dinner at his house. I remember his daughter, who married an astronomer at Dartmouth. Then he ended up at Mount Wilson helping with the design of a telescope later on.
You went to Tokyo, you went to Australia, you went all over the place, do you have stories that you like to tell (Laugh) about your experiences?
I had good experiences in most of those places. I was bringing them something that they wanted to give a try to. They may have been skeptical about how it would work or how they would use it, but I was treated well and had wonderful trips. I took an image tube spectrograph to Mount Stromlo and left it there for a year, because [Allan] Sandage was coming in and he was supposed to use this equipment after I left, and he did. I went to Tokyo from Mount Stromlo. I’m quite sure. It must have been the first trip to Stromlo, because I remember flying up to Japan, arriving in the middle of the night. The plane was late. (Laugh) Sleepy astronomers meeting me at the airport. (Laugh)
But, they met you at the airport?
They met me. And they had a truck that took the equipment. And, the truck took the equipment from the airport to the observatory. The astronomers took me from the airport to Tokyo for a day, and then we had a day of sightseeing in Kyoto, and then ended up down at the observatory. It was quite a nice visit. There were nice young astronomers, postdocs or whatever, there. Some of them had spent time in the States and I had met them when they were at Goddard. And so, there was a reunion of at least one or two of these astronomers, and that was nice, and they took good care of me. We got down to the observatory and started to put all the stuff together, but it turned out that the pickup truck had had an accident between the airport and the observatory.
Anyway, the truck was banged up a little bit, but all the boxes looked fine. So, we unpacked things and put it together. I think it was a Coudé spectrograph setup, so it was easy to do. They had a system at the observatory where the telescope operators, the night assistants, were also their instrument makers. They had a lot of cloudy nights. (Laugh) So, on cloudy nights the instrument makers would go to their lathes and build equipment, and on clear nights they would go out with the astronomers. We put all this stuff together and it was the moment of truth. We turned it on, and the tubes fired up and worked perfectly, and we were able to do astronomy. The astronomer was Asada. [Yoshiaki Asada, department of Astronomy, Kyoto University] And, he had young astronomers working with him, and they explained to me that they were his disciples. (Laughter)
Oh, yeah. Oh, yes.
Which was about right. The observatory was well staffed. They had a photographic technician, who would take care of doing the photographic work. They had an electronics technician there during the night in case some electronics needed attention. They had graduate students around who would run errands. Most of the time, this group would sit around drinking cold cider and listening to Joan Baez records. (Laughter)
No kidding? But at least they had a soldering iron?
They had a soldering iron. Yes. They had an instrument maker. They had guys there who could rebuild this equipment when they needed to. Anyway, we would work all night, go to bed, sleep a little bit, and then in the morning one of these graduate students would come and wake me up, we’d have some breakfast, and go out and spend a little bit of time sightseeing before coming back in the evening. Years later, I got a letter from the Professor Asada, who complained about the high cost of RCA image tubes. And, I pointed out to him that the cost of the Nikon relay lens that we were using for [the] photographic (Laugh) phosphor screen had gone up even more, (Laugh) but still it was the best thing available and we were buying them. And that, that sort of ended that episode, but it was a good experience going to Japan.
So, were the tubes provided at no cost, or was it just a subsidized expense to the observatories?
The observatory had no expense. We built the stuff here. We got to the point where it was too much to ask our shop to turn out all of these brass cylinders. I had a contact over in Alexandria, at their shop, and they did the bulk of the machine work in that the shop over in Alexandria, and NSF paid for it. I bought the lenses. The Image Tube Committee contracted for the tubes. I would test the tubes and check them out. I think we built all of the voltage dividers here. But, when a place like Yerkes, or Wisconsin, or Mount Stromlo got an image tube they got the works for free.
And, who decided? Was that a committee decision? Did the demand exceed the supply or did every observatory that wanted one eventually get one?
There was discussion. There was not an overwhelming demand for them all at once. There was a lot of interest. Everyone wanted to know what was happening with them. Tuve had his own ideas about who could make good use of an image tube. He had his own prejudices. So, it was a committee decision, tweaked quite a bit by Tuve. I had my ideas by then, people I wanted to work with or could work with.
Louis Brown identifies a Carnegie/NSF Allocations Committee that was formed to decide on the distribution of the remaining tubes after the first ones were distributed to the ones that I believe RCA made twenty of them. Then you prepared a tested operating system that included magnetic focusing, high voltage, transfer optics, associated hardware for each observatory, and the first one was installed February ‘65 at Yerkes. Then, Kitt Peak, Lick, Lowell, and Mount Wilson. So, those are the ones that were high priority. The rest went through this Carnegie/NSF Allocations Committee?
Yes.
When you made decisions about where these tubes would go, were you making decisions based upon the quality of the staff? Were they choosing to address standard problems that everybody else had been doing, only doing it quicker, or was it something they couldn’t do without this thirty, twenty, thirty, forty times increase in efficiency?
Right off hand, I don’t remember any influence on what the people were doing. It was more whether the telescope could carry the weight, whether they were going to use it as a Coudé spectrograph, or you could mount something heavy. Whether they had a spectrograph from which you could hang an image tube. We were not going to furnish spectrographs to every place, although we did lend Mount Stromlo one for a year, and Las Campanas still has one, as far as I know.
Because you said there were three of them (Ford: Yeah.) built. And, we have one of them. [shows the image tube spectrograph _Ford-Spectrograph.avi]
Lowell has one. I think the third one must still be at Las Campanas. I don’t remember the observing program of any astronomer or observatory really entering into it. It was more whether they had the equipment that could be adapted.
Okay.
At Stromlo, a lot of the interest came from Ted Dunham, who was an old-timer, had been at Mount Wilson, maybe with mixed success. I’m not sure.
Well, he was their instrument guru.
Yeah. Delightful guy. And, he was at Stromlo, and he came here. I had a wonderful photograph of Ted Dunham standing by my drafting table down in the office there. I’m not sure if I could ever find that again. It’s probably in an attic up here, (Laugh) unless it’s been thrown out. Anyway, Dunham knew what to do with the image tube and some of it might be built with plywood rather than brass, but he would (Laugh) get it done and it would be non-magnetic. And, he was fun to work with.
Did the two of you ever commiserate over being instrument men?
No. Dunham always had a problem that he was working on. He had some lovely Coudé plates that he was going to digitize, and work up abundances or some such thing. He was carrying these plates all over the world looking for just the right digitizing machine. (Laughter) I do not remember any points of issue with Dunham. That part worked very smoothly. At Stromlo in particular there was a Polish guy in charge of the shop or the instruments. His name may have been Kurt Gottlieb, and he rubbed some people the wrong way, but he and I got along fine. We got things mounted and running, and I don’t remember any problems with Gottlieb. When I talked with other astronomers who had spent time at Stromlo, they could remember issues from how things were done.
Coming back here, after this sojourn delivering all these tubes, is it accurate to say, then, that is when you, then Tuve started directing you or got you together with Vera Rubin?
Well, I think we were already together. I remember coming back from trips installing image tubes and meeting my wife in a New York airport, and she had a change of clothes for me because I was flying to Flagstaff to meet Vera to have an observing run. We started out working on the QSOs, and that was a pretty intense thing. We did not miss observing time, for trivial reasons, like installing image tubes. (Laugh)
So, that started taking priority?
Yes. And even more so later when we got into the M31 work.
So, the very first work that you did was simply higher dispersion, higher accuracy work on QSO nuclei, or the QSOs themselves.
Yes. Both that and the fact that these tubes had a sensitivity in the red that the photographic plates, did not have. So, we could confirm red shifts by picking up the red-shifted H alpha line down at 7,000 angstroms, or something like that.
So, again, the characteristic of the tube helped decide what—what would you do with it?
Right. Our frustrations at that time were with the whole 69-inch telescope, which had been used for stellar astronomy. The setting circles where the big counterweight wheels on the declination axis that had nice fine graduations. But, it was hard to do precision positioning of that telescope with those setting wheels.
Certainly by today’s standards?
By today’s standards.
But even, even at that time.
Eventually the telescope was equipped with modern sensors and you could read out the position on lights on the console.
And we’re talking mid to late ‘60s?
Mid to late ‘60s you were out there trying to set the Vernier on the declination axis to get that right.
That, must have been an interesting experience for you? I mean, you talked about the soldering iron. The atmospheres, the atmosphere for working at an observatory must have appeared to you to be pretty arcane?
(Laugh) Well, there was a lot of sophistication going on as far as what you did with your photographic plates.
Oh, sure.
The hyper sensitizing, keeping the plates cool. We had a refrigerator down here where we’d store our IIaO plates, in between runs.
This is all chemical based?
The shop people would keep their lunch on the upper shelves, but we’d have photographic plates. (Laugh) Finally, I think we got our own refrigerator for that.
But that’s pretty old technology. You’re talking about setting circles. You’re talking about direct photography. You’re talking about the way that Hall, if that’s right, took the films of double stars?
It was Frederick.
And then painstakingly?
Yup.
Did you have a feeling that, that there was a lot the technology could do to ease (Laugh) the burden of the astronomer at this time?
Yes and no. I have several memories of about that period and have to sort through it. There was just beginning to be talk of space telescope and everyone was saying, “Oh, we should build a space telescope. Think of the double star work we could do.” And, you know, I had been seeing all the work done at observatories and I knew that maybe there were a few thousand dollars of work, of support for double stars in the country, (Laugh) and, “Why would you build a space telescope just for that?” Here Frederick was doing it with, on a shoestring. Someone else had bought the image tube. So, there was that aspect of the technology. I don’t know. I think we were just too much focused on trying to get better photocathodes or better phosphors out of RCA, and doing what we could with them.
That sort of dynamic with the commercial side of it, I know that was a real pain for people at SAO, who were working with Vidicons, trying to get the Vidicons working for their space telescope, their Celescope.
Uhm-hmm.
This was very much around the same time as you were working, and it was very frustrating. It was absolutely essential, though, to have electronic readout. I mean they couldn’t have a photographic --
No.
—readout. But, it was that contact with Westinghouse, contact with others. Did you actually visit, let’s say, RCA, or Westinghouse, or GE?
Many times.
And, when you did visit, what did you do? Did you go right into the shop? Did you work with them?
I sometimes went up to RCA with Tuve. I think I always went to Fort Wayne to ITT by myself. I had good contacts there. I was pretty much working with the engineers. My background in solid-state physics was probably just the right level for working with the people who were building the tubes. We had a common language there. I remember Mr. S. F. Essig at ITT telling me, “Now, this is good, good work that we’re trying to do here, but you must remember our job at ITT is to make money.” (Laugh)
That’s part of the tension. Exactly.
But generally, we had pretty good relations with ITT and RCA. We did some work with Westinghouse. Most of that went smoothly. Some did not go quite so smoothly, but it worked out.
But, you found that a key ingredient in this was personal contact, visiting them?
Personal contact and having money that could buy tubes from them. Because these were research labs and they were making prototypes, and if they could sell one then that was a feather in their cap. That was a good mark for them. So, they were happy to see us.
In the SEC Vidicon story, the question was, “Who could actually manufacture enough of these tubes so that you got one or two of them that were acceptable?”
Uhm-hmm.
Now, that indicated to me that it was still something of a black art.
Uhm-hmm.
To what degree were these tubes the same? Because, of that first one that Louis indicated, the No. 57 I think it was, took only up to No. 107 before you found one that was acceptable. I mean, were you involved in that approval process? Do you remember that particular?
Well, I’m not sure what you mean by the “approval process.” I think I was the approval process. I had the optical bench. I had the standard sources. I did the evaluation.
You’ve mentioned the Vidicons. I think that something that Lou Brown didn’t quite get right or didn’t emphasize as much was that a lot of Carnegie effort went into evaluating the TV systems. This was mostly done at Mount Wilson by Baum and a young technician that he hired. “Young,” he’s, I don’t know, he was in his thirties or forties. He was an ordained minister and finding an ordained minister at the Santa Barbara Street, Mount Wilson, was kind of, interesting experience. (Laugh)
I would think so.
But they went through a test on all these exotic scanning devices, the Vidicons, the Orthicons, a lot of it on the Mount Palomar 20-inch telescope, and you’d send off a report to be typed and (it would always come back as, “The Palomar 200-inch telescope.” And you’d go back and strike one zero.
I know. You mean the prototype?
Yes. I think it was a prototype, site testing telescope.
Oh, site testing. This is on page eight of section twenty-three of Louis Brown’s draft part of this. He said, “By ‘63, RCA fabricated more than a hundred of these 70056 cascade tubes, constantly making modifications, and only No. 107 met the demands of the committee.” So, that meant you?
That meant me, but I think that Lou was reading too much into some poorly written report. I suspect that this, that numbering sequence started at one hundred, not at one.
[The two-stage, magnetically-focused tubes made by RCA for Fort Belvoir was called the C70056. Initially they were built with S-1 infra-red sensitive photocathodes and green P-20 phosphor screens. They were for night vision work and perhaps hundreds of them were made. We had a few made with other photocathodes and blue phosphors.]
Okay.
Uh huh.
But this is not to be confused with Baum’s work at Mount Wilson?
No. It’s not to be confused with it. Two separate things. All I’m saying is that Bill Baum did a fine job of evaluating the various scan devices, identifying the real problems and limitations, and pretty much saying, “I don’t think we need to do this.” And, others eventually reached the same conclusion. Bill Livingston had the most advanced Orthicon system at Kitt Peak and he and Roger Lynds finally gave up on it. It just wasn’t competitive with what was coming along, and other devices.
Actually, this is something I wanted to ask you about that, as what was coming along in other devices. Those are the solid-state detectors?
That’s much later.
Oh, okay. What was coming along then?
Other methods of doing your electron multiplication. There were the secondary emission tubes. The ones with barrier, with multipliers along the line. Some of these…
But is that the SEC Vidicon?
No. These were imaging devices rather than the scanning devices.
Okay.
And, some of these were made in England. They were done by people who had gone through McGee’s graduate program at Imperial College and gone into industry. So, the English Electric Valve, EEVs, and something called 20th Century Electronics. These were the high-gain tubes. These were tubes that made a big scintillation for your photoelectron. And then the question was, “What do you do with that?” Because, if you put a photographic plate in the camera there, the plate gets black very quickly.
Yes. (Laugh)
And, one solution that Roger Lynds and Bill Livingston utilized with great success was to move the photographic plate [perpendicular to] the spectrum and widen the spectrum on the plate by moving the plate. You’re looking for weak lines. You’ve got the continuum. You’ve got some absorption. You’ve got light-sky emission lines, but you’re looking for these weak lines from your QSO, your quasar and, a line will make itself visible with just a few spots if they line up. You can get some spurious lines that way on some. And, just a few of those spots, and the locus of points of which would make a line, give you something your eye can focus on and identify.
Even in the photographic period, you had a widening method of moving the plate up and down?
Well, generally, that was done by moving the star along the slit. And it would show up. The plate was so wide.
That’s right. How would you characterize this era: would you say [the Carnegie tube] became the dominant image tube for applications in astronomy?
I’m a little reluctant to use the word “dominant.” It was certainly the one that was used for research, and would appear in published papers with astronomical results. It was not the only one. It was certainly the one that was most readily available to an astronomer trying to do his work, his or her work.
Right.
I think at one time I started keeping a list of papers in the ApJ that had been done with a Carnegie tube. Usually you only have to look at the last paragraph to see the acknowledgement.[6]
Where they’d thank people.
How many did you get up to? How many did you count?
I don’t remember. But the numbers are here. I suspect Lou Brown’s numbers are accurate. They were in the forties, I believe, low forties.
Well, there is a testimony in 1965, in a Sky & Telescope article that says, “The Carnegie image tubes effectively ushered in the age of electronic imaging at many observatories. In addition, they revolutionized high-dispersion spectroscopy in the near infrared. Grateful observers cast aside bulky and slow photographic plates, painstakingly hyper sensitized with smelly (Laugh) and dangerous ammonia in favor of the new detectors.”
And, that was in Sky & Telescope?
Yes, Sky & Telescope, 1965.
Amazing.
And, they reprinted it that was one of their highlights. I remember seeing that.
Okay. Okay.
You were designated chairman of the Astrophysics Section here at Carnegie in 1966.
That’s the [Ellis] Bolton era of directorship here. Yup.
Okay. And, when you received the Washington Academy of Sciences Award in 1970, the description was, “It is not common for a young physicist to devote his scientific career to aiding the scientific community at large, yet this is just the role that W. Kent Ford, Jr. has accepted for the international astronomical world.”
Wow. (Laugh)
Okay?
Okay. Maxine Singer also received an award that night, except she was not present. And, Phil Abelson accepted the award for her. And, Singer later became president of the Carnegie Institution in Washington.
That’s true. That’s true. Now, is there a connection here? Is there a causal thing going on?
No.
There certainly is this very lovely recognition and, and it is an important watershed period. I’d like you to reflect on that, at this point. The question of the role of instrument development in professional astronomy.
I think Tuve was very much what we would call a “bench scientist.” He wanted someone at the workbench with instruments that were being built, or developed, or something. He was not that much of a paper pusher. I think he respected theoretical work, but that was not his thing. He was really happy when he could see Burke and Firor building a radio telescope with their own hands, with the gardeners, and the yardmen from DTM on call to help dig postholes or something. You know, he wanted the people to go out and get their hands dirty. That attitude prevailed in the image tube work. He wanted us to use these tubes to do whatever we found interesting in astronomy, and he was supportive in that. He would come out and visit us in Flagstaff when we were working out there. He made a trip down to Kitt Peak with Vera and me, I think. Yeah. Vera, the three of us went down. He was skeptical about big science. He had his reservations about a national observatory, but he was interested and supportive, and he went with us on that trip. The main upshot was that he said, “This old Jeep that you have, Jeep station wagon that you’ve been using for carrying equipment from Flagstaff to Tucson is getting old and you need a new vehicle. You should buy yourself a Suburban.” (Laughter) And so, we said, “Yes, sir.” And we bought a Chevrolet Suburban in Flagstaff and left it out there.
Oh, right then and there?
Within, certainly within the next observing trip. The Jeep was given to Lowell and was rebuilt and was still there the last time I went by Flagstaff. (Laughter)
But, this sense of building the instruments and making them better, we’ve interviewed Jerry Kron, Al Whitford, people like that who grew up under Stebbins, and continues to be an interesting topic for historians characterizing how astronomy changed So, my next question is, when did you feel that you had become an astronomer?
Ah, a good question. Well, when I started working with Vera, I suppose. We were doing these red shifts that were competitive with the red shifts that Sandage and Maarten Schmidt were doing out on the West Coast. Certainly, by the time we got into the M31 project doing the rotation curve of Andromeda.
Did Vera or anyone else, as you were sitting around thinking about, “Well, what will we use this new technology for?” ever simply come out and say, “Wow, we have the technology to do something that nobody else can do. Let’s do it.”?
I think I would have to say that we were both discouraged by the competitive aspects of doing redshifts. Lynds and his colleagues at Kitt Peak were, [and] had what seemed to us unlimited access to telescopes. They really didn’t, but it seemed to us that way. The 200-inch was cranking out lots of good stuff. We had some positions from the local radio astronomer interferometry effort. I’m not sure we ever really made use of that as much as we could have. But, it was competitive, and we were, neither one of us was happy about that. Vera was the one who was kind of steering that part of the work. So, she said, “Let’s try to do M31.” Well, I knew about Baade’s HII regions. Vera thought we could do them. I think we had spent some time at the Perkins telescope just looking to see if we could see these things visually.
Uhm-hmm.
And, they were pretty hard to see. We realized that we had a real, real problem if we were going to try to do that program.
With the 72-inch?
With the 72-inch.
There was a problem with finding charts. We had made an attempt to get copies of Baade’s material from Mount Wilson, and I think Vera had written the photographer, Bill Miller for copies of this stuff. Had gotten a reply that, “Well, I can’t really tell what it is you want, but if you’ll let me know which plates you want copied I’ll do so.” And, that really wasn’t what we were after. We were after material that we could get our hands on to measure offsets.
Right.
So, we cooked up a scheme where we would go back out to Flagstaff to the 40-inch Ritchey-Chretien telescope [which] has a large field that, using modern plates we ought to be able in the few observing trips to get enough plate material on M31 that we could measure our own offsets using Baade’s coordinates, and use that to find these HII regions. And we got time to do it, so we went out to Flagstaff, cold, windy November, and we’re working away. Got some plates. The images were kind of fuzzy, but they were plates and we could probably distinguish the HII regions. Jerry Kron, by that time, was director of the Flagstaff Station of the Naval Observatory. He came over and said, “Well, what are you doing?” He had approved the observing request, but he said, “What are you doing?” And, we explained that we were trying to find a way of identifying Baade’s HII regions. He said, “Oh, years ago I worked on that. I tried to do photometry of those. And, you know, Henrietta Swope at Mount Wilson has all that material and all we’d have to do is go ask her for it.” Well, these were the days I was still making frequent trips from Pasadena to Flagstaff, and from Flagstaff back to Pasadena, and we’d often have lunch with the astronomers, which included Henrietta Swope. So, my next trip to Flagstaff I went over and took this train from Flagstaff to Pasadena.
Oh, yeah, I know it.
The Super Chief. Paid Henrietta Swope a visit and she said, “Yes. I have that material here someplace.” And, went fumbling around and pretty soon came up with just what we needed. And, at this point I cannot remember exactly what it was. I think they were contact prints of plates on which Baade had written his designations.
I’ll be darned.
And so, it was a secondary source. They were contact prints and they were in good shape. She said, “Yes. You can take these and copy them, but we’ll need them back.” And so, I took a whole stack of this stuff back to Flagstaff. Hall was there as director. And, Lowell had a very good astronomer, whose name was Jones, a photographer, Stuart Jones.
Photographer at Lowell Observatory.[7] And, I explained to him what we wanted and then what I had, and he took those contact prints and some special emulsion on a stabilized backing and copied them again, I think again a contact print. And so, we ended up with things that looked just like Baade’s plates. And, I put all that in a green notebook with plastic separators and things, and from that Vera was able to measure offsets from stars that we could see to the HII regions. But then, we had to go out to Flagstaff and get to the telescope and do something with it.
Do you have more photographs there or do I have to dig into my stack?
Which photograph?
[Following passage set has accompanying video clip, to access please contact nbl [at] aip.org]
Well, the spectrograph. This is a good one. This is after we have made the change. This is the spectrograph from here down. This is one of the later image tubes and this is with a camera that Dr. Bowen designed for us, because I recognize the mounting there. But, the problem was how to offset from stars that we could see up here to these HII regions, which some of them we could just see a bit of fuzz, but really couldn’t do much with. So, I got busy with the guys in the shop and made this two-coordinate measuring engine. It mounted on the guide box. This guide box is a mirror at forty-five degrees that brings the light out, but it has a hole in it so that when the mirror is moved in the open position, the light goes from the telescope, goes through the hole to the spectrograph down here. But, if it’s the other way, it comes out the eyepiece. So, you see the field here, a mirror image of the field, or something, and you can do north-south offsets. Or, if you’ve rotated the spectrograph you can do offsets in a different coordinate system.
Is that you as the observer there?
That’s Vera.
That’s actually Vera. (Laughter)
Oh, that’s Vera? Okay.
I think she may be wearing my jacket. (Laugh) But…
Okay.
I took the picture. Anyway, we built this thing and got it so that it didn’t wobble and didn’t flop and…
An X-Y offset?
X-Y offset. And, took it out there and it, by that time it was late in the year. I believe it was in December. And, we’d have a few nights on the telescope and Vera had done some measurements and had some coordinates and we first of all got the scale of the telescope by measuring between the stars that we could see, and used that scale to scale up our offsets, set the thing, and got a, made an hour, hour and a half exposure. And, took it to the darkroom and developed it, and we could see the emission lines. We could see H-alpha and nitrogen lines. There was plenty there to measure. That was a great, great thrill. That was the, really the wonderful instance, because we knew that we could do the program.
You did it?
Just given enough telescope time. Yeah.
Yeah. Exactly. I can imagine that. That moment must have been very poignant.
There’s a kind of a sad or amusing afterward to that. We had a visiting astronomer with us, by chance, that night. And, we left him in charge in the darkroom to rinse the plate and set it up, and the rinse water turned real hot. It was not a temperature-controlled bath.
Oh, no.
And, we lost the emulsion. But, it didn’t matter, because we knew it would work.
You knew it was there?
Yeah. It was interesting because we had talked about this program with Sandage, and Sandage didn’t think it was a program worth doing. And, it was not something we should get involved with, because he realized it was going to be a long project. It took us three years to do those HII regions. And, he spent a fair amount of time, I think, on a flight back from an IAU meeting, maybe the Hamburg meeting, telling Vera that, “The French are building an interferometer that’s going to be able to do this in just a couple of nights work, and they’re going to have the problem solved before you get there.
An interferometer?
Yes. The French had great interferometer activity about that time.
This is an optical interferometer?
Yes. Optical interferometer. Anyway, we went ahead and plugged away at this for quite a long time and got the results.
What happened to that interferometer?
I think it always gave ambiguous answers. (Laugh) I’m not sure.
Who was that?
Okay. I don’t know. Labyrie --
I’ll look for that. I have an image here of the spectrograph we have in our collection that’s on display.
Oh, yes. I want to talk to you about this. Where did you get this spectrograph? Did Louis Brown bring this down?
We found it in the attic… here. On two occasions. I saw it first in the attic. I can’t remember whether it was Lou Brown or who I was with, but then the next time I saw it, it was in front of Vera’s office. (Laugh)
Okay. That’s the Bowen camera. I can tell that because the Bowen camera had a focal plane that was slightly tilted to the axis, and so the whole image tube assembly was cranked over, and there’s a micrometer down here that you use for determining that angle. But, this thing you would unclamp it, adjust it to give you a flat field of focus across the photocathode, and then you clamp it up again. It was a Cassegrain-Schmidt camera. I’m sure all the optics are still there.
[Following passage set has accompanying video clip, to access please contact nbl [at] aip.org]
What is this entrance?
That’s the entrance, and that’s what I wanted to talk to you about.
Right.
This thing has no business being there. That’s a one-inch telescope that was used as a focusing mechanism. We spent a semester doing beam-foil spectroscopy with the Van de Graaff here.
Oh, this is a laboratory device? (Laugh)
So, to image the foil from the Van de Graaff over there, onto the slit of the spectrograph, we needed a telescope. And, we mounted a lens in a tube in this focusing device and we’d reimage Lou Brown’s Van de Graaff beam over to the slit of the spectrograph. So, that really should be taken off. I believe there’s a plate there. There’s a separate plate, and that was just part of the support system. This spectrograph was on its side, up in the air, and that was what supported the thing.
So, that’s not part of the X-Y?
That’s not part of the X-Y. It’s not part of what was used at the telescope. It was a laboratory experiment over here on the Van de Graaff.
Okay. So, then we should take that off?
You should take that off. I’ve laughed about that every—I’ve seen the thing twice down in the museum, and I’ve laughed at it both times. I thought maybe Lou Brown had stuck it, or kept it on there just to pull your leg a little bit, (Laugh).
Well, he could have. (Laughter) He was a good friend.
He was a great guy.
Okay. But, other than that, as far as you know, it’s complete?
Yeah. It’s full.
There should be a tube in there?
Yes, complete. And, I think you’ve got a voltage divider mounted on the back here.
Well, this is the stand it came in.
And, that’s the way we pushed it around the observatory floor.
When we first acquired it we loaned it back to you, because the Carnegie had a display down on P Street.
Oh, yes.
The [Carnegie] centennial, right.
And, that’s the way it was displayed. (Laugh)
Okay.
Wow. I don’t think the exhibits personnel would have had a clue about that.
But we can easily make that alternation.
Well, it’s true. That’s the way it was used here. As to which spectrograph is which, that’s a good question. These spectrographs were swapped back and forth as new camera optics became available. I have to be careful of what I say here because I’m really kind of vague about this. I suspect that this is one of the earlier spectrographs, but I’m not sure about that. It certainly had the modern optics on it, the Bowen optics. I don’t think it makes a whole lot of difference. The spectrographs were essentially identical.
Okay.
I could not tell one from another, if you lined three of them up here.
Okay.
Okay. But, we should take that off, and that certainly is something we can do.
And, if you take that off you can just look right down and see the slit and the mechanism for the comparison lines.
Right. I was wondering where that was.
[Following passage set has accompanying video clip, to access please contact nbl [at] aip.org]
On the other photograph here, this is the timer for comparison spectra.
Here, let me start the—okay.
The little timer that’s on the…
That little box?
Little box with the clock face.
Yeah.
Is just a darkroom timer that we used to switch on the comparison light that went in through the comparison prisms.
Right. I thought that was a pretty…
The box below that is a light-box with a red filter and that’s where we could put our finding chart, a little rheostat on that.
Okay.
And, we could see our finding chart right there, and our eyepiece right there. And so, we could do these offsets with the chart, with the numbers, and the view up above.
Right. Okay. Well, that’s very, that’s good to know. That’s a nice bit of observing style, observing technique.
Uhm-hmm.
Okay. How can we go about confirming exactly what these tubes are?
33011s.
Okay. I think what we should do is, before I leave today, Shaun, if you have any more of these image tubes, I can take a look at them and tell you what I think.
I know this is all I have in our archive.
Okay.
But, if there are more in some storeroom you’d have to ask the astronomers.
I doubt it.
Okay. So for, even though earlier on you did identify these as the thirty-threes, we’re now wondering whether they are or not?
Oh, no. These, I would call these 33011s. They were the first Carnegie image tube, and they were the ones that were first distributed. My recollection is, and I’ll check this for you by going through what I have, is that the 056 was either an electrostatic tube or an infrared tube. I think the, if it had an “E” on the end of it, it was probably and infrared tube. And, I think this label does have a E.
Yeah. It does.
I can check that for you.
Can you give us a little insight into your personal life, to the extent that you would like to record it? (Laugh)
Came back from an observing trip in late April or early May, Flagstaff, from Flagstaff in 1961. Carnegie has an annual meeting down at P Street and I went to the annual meeting, soon after returning. And, by this time I’d had enough contact with people at P Street through NSF contracts and things, that I knew some of the people down there. And, one of the lovely secretaries, she was the secretary to President Haskins, was there at the door, and Ms. McCollum said, “Oh, Dr. Ford. I’m so glad you’re here. How have you been?” And, I said, “I’ve been fine. I’m just back from Flagstaff. Had a wonderful, wonderful trip. I had good weather. I got clear skies, good seeing, and it was just a good trip. Because at the end a couple of us went off hiking overnight and hiked into Rainbow Bridge. And, this is quite an impressive structure now. I’m a Virginian and so I know about Natural Bridge, but Rainbow Bridge is a big, big rock. That was really a good trip.
When was that?
(Laugh) I want to tell my story and then I’ll try to figure out when it was.
That’s fine.
I said this was good, good hike in, and at that point there was this sweet young thing standing next to Ms. McCollum at the entrance of P Street. And, my story is, this sweet young thing said, “Oh, I’ve always wanted to go there.” (Laugh) Rainbow Bridge. And, I said, “Oh, really?” And she said, “Yes. My brothers have spent a lot of time in the summer backpacking with mules out in the West. But, I’ve always wanted to go to Rainbow Bridge.” Well, I said, “That’s interesting.” And, I went on. But, by the end of the evening I had taken her several cups of champagne with strawberries floating in it, (Laugh) and I went home with her phone number.
Oh, well there you go. Okay. That’s a good story.
And, yeah, we hit it off pretty well. I think she was a little shocked to find that I had a son at home and no wife. But, she probably had figured that out by talking with people at P Street.
I would think so.
I think she had my resume and she probably knew more about my official records at P Street than anyone else, by that time. Anyway, we got married. There’s a side point as to when Vera came to DTM. I had a conversation with my wife, Ellen, and the present DTM director, about when Vera came here to work. Ellen remembered that it was after our child Russell was born, but I think she was wrong about that. It was after our child Jeanette was born. It was a different time, and I think the Year Books are quite accurate as to when Vera came, even though at the time when we were talking we remembered going to dinner at Vera’s house, soon after she came to work there, and went home and Ellen proceeded to go into labor. (Laughter) But, that was with Jeanette.
Well, Kent, you’ve talked a lot about Merle Tuve in the time you’ve shared today. How did things change for you or at DTM after Tuve retired? That was 1966.
Okay.
You’ve worked for subsequent directors…
Well, Baum and I were working closely together at the time, and we used to laugh about the difference between Dr. Tuve and Dr. Bowen, who was the director at the Observatories.
Ira Bowen?
Bowen. I was very fond of Dr. Bowen. We had a good time working together on various problems. But, he was very different from Merle Tuve. He would think things through in great detail before engaging in work. Tuve wanted to get started and they were just different personalities about going about work. Tuve was, “Let’s do it.” And, Bowen was “Well, let’s see if this is going to work. Let me think about this.” And he had good ways of working out problems. And, it was a very valuable insight particularly if you were taking something to a place as sacred as the Coudé spectrograph of the 100-inch. You wanted things to work right up there. Bowen would know how to make it work right. That was good. [Ellis T.] Bolton was the [DTM] director when Vera and I started doing our QSO work, and did our M31 work. Bolton was very supportive of us.
Bolton or Bowen?
Oh, I’m sorry. Bolton was very… supportive. He had only a casual background in astronomy, but he was learning fast. We tried to bring him up to speed, but we would have to go to him for money to go to Flagstaff, money to buy gratings for our spectrograph. And, he was interested. He would sit and his office was right over here. And, if we went up with a problem like needing to go to Flagstaff, or needing a new grating, you could spend a lot of time talking about it. He wanted to get all the details and wanted to make sure he understood it. And, it was time consuming, but time well spent. So, Bolton was okay, as far as I was concerned. Bolton had Tom Aldrich working with him as associate director. And, Tom was more into seeing how things got done and this, of course, ruffled a few feathers from time to time. But, the two of them together, I think, did a fine job. I think later on, Bolton maybe started having more problems with other things, but by that time I was off for two years at Kitt Peak. I had a sabbatical. Carnegie doesn’t have sabbaticals, but I had a sabbatical or a leave of absence or something to spend a year at Kitt Peak, and I ended up spending two years out there. Carnegie, paid half my salary. Kitt Peak paid the other half. And, that was when they were bringing the 4-meter telescope online. They had a spectrograph, but no image tubes for it, and they wanted me there to make a user-friendly image tube camera for the spectrograph, which I did. It was great experience. It cured me from wanting to work for the government for (Laugh) some time. But, we had a good time. We went out there for two years and we had two young children, by then who were in the Tucson school systems, and Ellen was interested in taking up her childhood hobby of riding horseback.
That’s a perfect place for it.
She got a horse. The kids got ponies. So, it was a good experience for the whole family.
This must have been in the early ‘70s?
The ‘70s. Yes. Seventy-three, ‘74, I believe it was.
The 4-meter.
I was away for those two years. I was back here occasionally, because we’d come back in the summertime and, of course, I’d come through Washington, and have to come around and pay a visit. But they were fun because I was out there. When Vera would come out for our observing run, you know, I could have things all set up and ready to go. That was neat for both of us.
So, when you returned, this was close to the time that George Wetherill arrived?
He was just arriving. I had come back probably for a visit, on vacation or something, when the directorship was being discussed. I was met at the airport by Lou Brown and Vera Rubin, and somebody, maybe Selwyn Sacks. I’m not sure. And, they wanted to talk about who’s going to be the next director and did I remember George Wetherill, because I had overlapped with George here. And, my recollection of George was that, “Hey, this guy is a scholar. He’s a real student of science and he’ll be different, but he’s…” I had no reason to think anything else.
Well, I thought maybe they came out there to convince you to be the next director?
No. No. No. I was much too junior for that. So yeah, George was approached and came.
Did your work change after that?
Well, it did, but it was mostly because I’d been away for two years. (Laugh) I sort of lost my standing in the stack. But, it didn’t change all that much. They were getting into digitized astronomy by then. I got involved with digitizing images. We had to get money, the astronomers had to get money to buy the VAX-750.
The computer?
So we could do image processing. And, you know, I think Lou Brown skipped over this part in his write-up, but it was the astronomers who furnished the first VAX here, and shared it with the department.
Certainly by the late ‘60s, you were gearing up for digital…
Yes.
…work?
Yeah.
Did you look forward to the challenge? Was this something that you figured you could use your talents and interests for?
Well, the first thing that I got involved with was the image dissector scanner. That was a challenge. Sure. It was a challenge, mostly, just to get all the parts together and to get the image dissector running. But, eventually we did that.
But, was it a technology or a technique that was…
Oh, it was…
…foreign to you?
No.
Okay.
It was, well, the technology, to some extent, but it was just a photomultiplier with scanning coils. We had a friend in the image Orthicon business, whose name was Dewitt, Jack Dewitt, and he was down in Nashville and he was president, I think, of a radio, a TV station, WSM. It’s the station that used to broadcast and then telecast the Grand Ole Opry. But, he was an amateur astronomer and also an electronics nut.
That’s a good combination.
So he had built up an Image Orthicon system for his backyard observatory. And, at some point he brought his Image Orthicon equipment out to Flagstaff and I worked with him to hang it on the back of this Morgan telescope that we had there.
The point of this story is that Jack Dewitt had wound his own deflection coils for this image Orthicon on an oatmeal box, (Laugh) because it was stable, cardboard, and he did the winding. I was so impressed with this that I thought maybe I could find an oatmeal box just the right size for the image dissector that we had, (Laugh) and do something similar. I don’t think I had to resort to that. But, that was the hands-on approach to a problem.
I would say. That’s very nice.
So, yes, that was the first digitizing. Then we got into digitizing the plates. We had a scanning micro-photo-meter, and I had built that up. By today’s standards, it was a bit of a clunker, but by those standards it produced a digitized spectrum on a reel of magnetic tape that you could take to the computer and look at it. About the time the image processing and the VAX came along, we were getting into display systems, and we bought something called a Gould DeAnza display monitor and Mike Acierno had just come on board as a computer guy. Mike and I worked on coding the Gould DeAnza to display images from various scanning devices or from a digitized tape. That was interesting coding. We got it working and it worked for a long time. By that time Vera and I were interested in rotation curves of galaxies at the distance of the Virgo cluster. And, you could see the curves in the spectra. And so, the idea was, “Do you sit there with your measuring engine and crank along that, that line, or do you build a machine that takes the digitized image and follows it for you?”
Right.
And, I built some code that would trace a line, doing steps, and doing a profile, and finding the peak, finding the velocity, and moving to the next step. We had that rigged so that on the display system you would see the image and you would see the cursor moving along as it tracked the line in the spectrum. It was really kind of fun to watch. (Laugh) And a lot of the plates that Vera and I did on the rotation curves were done with that machine and so, I ended up doing a lot of computer work at the end. I did not do computer work at the beginning.
You were faced with a need to apply computers and at least in the way you described it was a pretty transparent process to learn coding and to start applying them, and it did not intimidate you. You didn’t have to find another person who could do it for you. Is that a fair description?
Well, the computers had been at DTM for a long time. In the period that we’re talking about, we had the IBM computer room down the way here. The computer was the IBM 1130. Then the geophysicists got into digitized seismic records, and they had a nice suite of computers up in the attic, PDP 11-34s or something. I started working with those computers and learned a little bit about coding. I was recording images on magnetic tape down in the basement and then taking them up and decoding those tapes on the geophysicists’ computers, the seismic computers, and getting whatever tracing out I could.
Well, was this some sort of early graphic language or was it Fortran?
It’s Fortran.
And, somebody taught you logic someplace?
We all took computer school when the 1130 came. I had an IBM…
Oh.
…class.
Well, Lou has a chapter in the book, which you probably don’t have access to, but it’ll give you a chapter on the computing at the department.
I only have a part of it.
Okay.
There were a lot of resources here. Not only did I learn Fortran language, I learned Spanish at DTM. The issue was that the seismologists were going to Peru and Chile and doing seismic work. David James was heading much of this, and Vera and I were going to Las Campanas, and Cerro Tololo, and we needed to have just a little bit of Spanish. And so, someone called up the Spanish Department at Georgetown. I think it was Georgetown. Spoke with the head of the department and told him what we were doing, that we were a bunch of scientists trying to get up to speed with Spanish, because we had occasion to use it, and did he have a graduate student who would come out and tutor us a couple of days a week? He said, “Let me think about that. I’ll get back to you.” (Laugh) And, he did. His wife was a native of Spain and she was just a delightful person. She came out and taught two classes, a beginning and advanced class, in the morning, and then she would come over and have lunch with us at noon, play ping-pong with us, and all in Spanish.
It was an immersion.
So Dave, I think, became very proficient. Vera was good. I learned enough to get by. I could defend myself and even make telephone calls in Spanish. (Laugh) And then after that I was in Tucson and did a little more Spanish, and we had Spanish radio stations in Tucson, in those days. I could listen to basketball scores and listen, keep my numbers up on that.
Kent, how did you come to the decision to retire? I mean, this was concurrent with a lot of change within DTM and the Geophysical Lab when the discussion began, and this is in the ‘80s, of well, “What is the future of the departments, basically, where are they going to go?” Do you want to say anything about that and how did that play into your decision to retire when you did?
That did not have a big role. It had some role. I had been involved with the design of the new building, in the sense of what we needed, well do you still need a darkroom? Were you going to do lab work? And, they had a lot of good problems there. We were not real happy. “We” being Vera and I. We were not real happy with the architect that was hired. We would make suggestions that we thought made sense, and he thought we were criticizing his design and, we really weren’t. We were just saying, “Well, wouldn’t it be better if we did it some other way here?” The one issue that comes to mind was the shop annex here had skylights and walls with windows, and the place where the astronomers were located was pretty dark. It had a darkroom there, the library was dark. The offices had windows. But, the architect’s scheme was to make an auditorium out of the old shop, because he knew how to make that shop dark. There would be shades that would go across the sky lights, and everything would be dark, and you could show slides. And, the lunchroom could be made bright, and it was, but it, you know, it just didn’t seem like quite the right way to do things. If you had a dark area, that’s where you should show slides. If you’ve got a bright area, that’s where you should eat lunch. It didn’t work out that way. I guess it’s been changed. We were just not real pleased with the plans for the new building. But, I was here. I helped move stuff over there and move the VAX out and over there and got it set up and running. As to why I retired, I had been here for thirty-three years. I was finding that doing night work, serious astronomy, was getting harder and harder. Flying out to the Southwest, getting on a night schedule, staying up all night, doing some work during the day, working all night, it was hard. Vera took to that much better than I did. (Laugh) And, also at that time, fortunately, CCDs were coming in. We could bring home tapes, and that was great. That was good data and I enjoyed that, and enjoyed working on the data. But, it wasn’t the same thing as having your own spectrograph or your own image tube there. So, I had lost a little bit of contact with that. I was more of a user at the National Observatory, or Palomar, for that matter. Another thing was that our kids were all off in college, or beyond. Ellen was free to take her horse down to Virginia and spend long periods of time on our property down there.
She would go down with the kids when school was out and stay through the summer down there, and then come back in the fall, and then during the summer I’d go down on weekends. The kids got off to college and she was staying down there until Thanksgiving. (Laugh) I would go down on weekends, or every other weekend, or something, and that got to be kind of tiresome. We wanted to do something better about that. So, I say in a laughing way, “I retired so I could rejoin my wife.” There was a grain of truth there, enough that we could laugh about it, but it wasn’t the only reason.
There were a number of things. I looked forward to the geophysics group [Geophysical Laboratory] coming here, because I thought they were doing some interesting physics. I wasn’t so interested in their geology or geochemistry, but I was interested in some of the geophysical techniques they were using. I thought that would be kind of fun to be around. I did not think it was a good idea to have a big lab. I thought that you would soon be spending too much time serving on the library committee and deciding which books you should buy for geophysicists, or geochemists, or seismologists, and which you should buy for astronomers, or how much time you would have to spend on a shop committee deciding whether shop time would be allocated to high-pressure physics or to building cameras. I think this was, in part, because I had spent time visiting a lot of observatories, especially those in England that were large organizations, more like the Naval Observatory. I had spent time at Kitt Peak, where there were lots of things going on.
My personal inclination was to go back to the darkroom or the workbench and build something. That was what I really enjoyed doing. So, there was this combination of the kids were away off in college. I didn’t have those tying us to this area. Ellen was spending more time with her horse and her ponies down in Virginia. I was reluctant to get involved with a larger group, but I think as far as I can tell that’s worked out fine. So, I’m glad. It was just time.
Your eloquent description of how you felt different bringing home the CCD data, on one level it was very efficient. But, on another level it wasn’t, if I can assume, wasn’t as personal? There was not as personal a touch? Is that a fair description?
Oh, that’s a fair description. But, I was better off than most people, because I was familiar with the VAX computer system. I had become the de facto system manager for the VAX system.
Really?
Yeah.
Oh, now, see that’s quite something. Yeah.
Well. That’s something Lou Brown didn’t put in his [book], (Laugh) he skipped over that part. He didn’t have room to do all these things.
The way that CCD systems are set up now, especially at national observatories, everything is very formatted and you simply sign up for time,…
Yeah.
…and you could actually observe from anywhere.
And, there are people doing it right here at DTM.
Of course. Does that appeal to you in the same way as testing your own metal, your own instruments, challenging the nature directly?
I think of the time that Vera and I were spending in cold telescope domes, (Laughter) the wind blowing, coyotes howling off on the mesa, we would have been happy to have a warm room to (Laugh) sit in, whether it was in Flagstaff or a lab back home.
Okay.
There certainly is a certain, I don’t know whether you call it a romance, but a certain tradition of astronomers going off and standing at the telescope getting their data. And, I think it’s some of us are reluctant to see that tradition just disappear and be given over to technicians who can set up the equipment for you at the observatory, and give you a data line to feed in.
It is the intimate association with the activity. And yeah, I mean you talk about the coyotes, and the wind, and things…
Yeah.
…like that. And, it’s not tangible. It’s an intangible.
Is it like the librarian’s problem of card files being digitized and now you can access the card file, presumably, from your desk downstairs instead of going up and thumbing through the old well-thumbed cards to find…
That has neither romance nor appeal (Laughter) to me.
But in the same way it’s a different form of browsing.
Yeah.
Yeah.
And, browsing a library physically and browsing it electronically, I can tell you, is very different. They both have advantages. They both have disadvantages.
If that makes sense. I have one more question.
Okay.
One of my collecting goals is to preserve this era of image intensification prior to solid state, what we would call the “vacuum tube era,” maybe, if you will. And, that’s approximately from the 1940s through the late ‘60s, ‘70s. Now, we’re sitting here with a number of examples and even though we have one of the tubes in the instrument, in the collection on display, we would not want to take that tube out of the instrument. So, we can’t actually display it itself. So, if you were designing a collection to preserve the technologies that were brought to it, what would be some of the absolute must haves in that collection? We have a Kron electronographic camera. I am trying to secure a Lallemand from Lick.
Merle Walker.
Merle Walker. (Laugh) At first he wanted to give me his entire laboratory and I said, “No, I can’t take that. Just one unit.” You know. And, I also wanted to be able to preserve, somehow, the stuff around it that made the thing work, that kind of thing. So, clearly the Carnegie tube is very important. I found a McGee Spectracon that I want to collect. My question is, as usual, is, “What am I missing?” To appreciate the evolution of the Carnegie project and its contribution, it’s important enough to get more than one example, possibly get an early example and another one that contrasts with what I have in the spectrograph. But, I’d also like to get one that represents the spectrograph and the sorts of things that it could see and do.
If you have any initial thoughts, I’d love to have them for the record. But, this is also a question for longer-term consideration and deliberation, and what else you may find.
Right.
Yes. I’m really surprised that you did not have one of the ceramic tubes for your display. And, I will, I’ll see if something can be done about that. [9]
To the best of my knowledge we do not.
Except what’s in the spectrograph.
Right. Of course. I have to do a little more tracking down inventories at other museums. You’re looking at the ceramic…
Yes.
…Carnegie image tube?
Yes. I think that was the 33063.
The 063? Okay.
And, it looks just like this, except it’s a little longer. But, it was made with somewhat different technology.
And, it has twelve, you said it has nine or twelve leads?
These have nine leads. The one that you have down on the spectrograph has twelve.
Twelve?
The 063 is a twelve.
Okay. Twelve leads. The one I have in the spectrograph is a 33063?
Yes, it is.
Okay. I was thinking of taking it apart and checking. (Laugh)
No, that’s what it is. I’m sure.
I will double and triple check, but it would be great to have a second tube in the collection for a display.
We’ll scour here more thoroughly.
That could be very helpful.
I probably have one that I could free up. I took one home with me. (Laughter)
Well, we don’t have to do anything immediately. Just want to…
Okay.
…make sure. Now, the other thing that you brought up would be the handling and traveling system for the membranes, for the barrier membranes. And, we can talk about that at some time.
Okay. I think I still have that and I’d be glad to get it off my shelf. What I have is the casket: an aluminum box carefully made at the Naval Observatory, and the little cartridges of film sat in there like records in a record storage box.
Okay. Well, for the record I want to thank you very, very much.
Right. Okay.
And, also for the record, we always do this at the end of an interview, we say, “This will be transcribed. We will edit to make sure that the transcription is fair, but we’re going to edit very lightly. This is a record of a spoken conversation.”
Uhm-hmm.
And then, we’re going to send it to you. And, we don’t expect immediate turnaround, but, you know, in terms of our careers (Laughter) we’d like to get it back sometime, so we could deposit it.
Right.
Once you read through and make corrections or changes, then we'll ask you to sign various permission forms.
Is there anything that you would like to note that we haven’t covered?
Exactly.
What strikes me, just glancing there are students and postdocs. We had some good students.
“We” meaning, you and Vera?
Uhm-hmm. Sandra Moor was the first. And then she became Sandy Faber.
Oh, yes. Okay.
She worked with us a summer. Chuck Bennett, Charles Bennett worked with me on various electronic problems, and probably the image dissector mostly. He’s at Goddard. He worked with Mather.
Yes.
He’s an MIT graduate. He was the guy who made their experiments work. (Laugh)
Yeah, that’s good to know.
Oh dear. We had an astronomy student from Ohio who was here for a year as a postdoc or two. Oh, I can’t think of his name right now. Went off and is up in the Schenectady area, at GE and so forth. We should have done this ten years ago. We had some good postdocs. Sandro D’Odorico. Well, you can go through the list, but the students that were here both in astronomy and as summer students working with the electronics have turned out to be pretty good. Sandy Faber built focusing magnets for me one summer here.
Great. That’s marvelous. And I know I’ve worked with Chuck Bennett in acquiring some of the COBE…
Yeah.
…hardware and things like that. That’s right.
Okay. Well, it’s been fun.
Great. Wonderful.
Seeing all these little image tubes.
Thanks so much.
[1] "SIT vidicon with magnetic intensifier for astronomical use," Colgate, S. A.; Moore, E. P.; Colburn, J. Affiliation: Applied Optics, vol. 14, June 1975, p. 1429-1436.
[2] "The Effect of Deposition Rate on the Mechanical Properties and Structure of Thin Silver Films Made by Vacuum Evaporation," Ford, William Kent, Jr. Thesis (PH.D.)--UNIVERSITY OF VIRGINIA, 1957. Dissertation Abstracts International, Volume: 17-11, page: 2644.
[3] O. C. Wilson, W. A. Baum, W. K. Ford, Jr., and A. Purgathofer, “A preliminary investigation of lithium in Main Sequence visual binaries”, Publications of the Astronomical Society of the Pacific, vol. 77, pp. 359-366, 1965.
[4] Ford MVI 0357 “describes tubes”
[5] [0]Covered in Ford - 1958 Tube...avi
[7]The ADS indicates that "Carnegie Image Tube" appeared in astronomical publications between 1956 and 2013, 775 times with a peak of 200 mentions in the period 1975-1979.
[8] Stuart Edgar Jones (1930-1989), chief photographer, Lowell Observatory
[9] Followup was made. NASM has an example of the tube.