Philip Abelson on his experiments with how to separate isotopes in potassium and uranium salt.

Crumpton:

I see. So you were running your own experiments late at night or something?

Abelson:

What I did, first of all I reviewed the literature about methods of separating isotopes. I went to the Library of Congress and found that there’d been success in some separations but they were separations involving elements such as lithium and carbon. But, finally I found an article by two Germans in which they had been able to separate isotopes of zinc to a degree, not perfectly, but to a degree and they had done in aqueous solution and they had used what was called liquid thermal diffusion to do it. I decided this was for me because I would see what I could do about liquid thermal diffusion. So, I more or less duplicated, the apparatus they had used. I didn't have a mechanism for doing isotope analysis of zinc isotopes, but there was someone at the Bureau of Standards who could measure isotope separation in potassium. So, I conducted an experiment with some potassium salt in solution and found I could verify that this method gave rise to a partial separation of the potassium. The next step was to try a solution of uranium salt. When I did this, what did I find in the bottom of my column, but a dirty mess!