14 October 1954

Dr. John Kendrew

Cavendish Laboratory

Cambridge

England

Dear Kendrew:

I am pleased to learn that Dr. Joseph Kraut may come to the Cavendish next year, to work with you.

He was here for three years, obtaining his Ph.D. During most of this time he worked on the determination of molecular weights of proteins by the light-scattering technique, and then for about a year on making x-ray photographs of feather rachis.

He is an able and well trained physical chemist, with a good knowledge of physics and mathematics as well as of chemistry. He is a hard worker, and has good laboratory technique. I have seen him only as a graduate student, but I would expect him to get something significant done during his year with you.

He knows how to take x-ray photographs, and something about how to interpret them. However, he is not one of our x-ray men - that is, he has not gone through the job of determining the structure of one or more crystals, and would need, I think, supervision in the interpretation of x-ray data, unless he has learned a good bit during the last year.

I am sure that you would not be disappointed in him, if you allowed him to come to your laboratory.

I am glad to learn that Peter is doing well with you, now. I had surmised from his letters that he was working harder, and feeling more satisfaction in his work.

If he continues to work satisfactorily, I should be glad to have him remain for a fourth year of research with you. I judge that you think that, if he continues to work, he should be able to get his Ph.D. in 1956.

I shall look forward to learning more about the results which you obtain with the finback whale hemoglobin, especially the form with chains parallel to a crystal axis. Also, I hope that the work with

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telluric acid is successful. I am pretty doubtful about there being any other inorganic substance that would react with hemoglobin in such a way as to attach a heavy atom almost directly to the iron atom.

I have been spending a large amount of my time during the past three months on the preparation of a new edition of my elementary textbook, but I have also been working steadily on the problem of the structure of collagen, and hope that the solution will be obtained before long. Corey and Marsh and I are publishing a long paper on the structure of silk fibroin. Our structure is, of course, a pleated-sheet structure, with the side chains all on one side of the sheet, and interleaving, as I mentioned briefly in my talk at the Solvay Congress. It differs somewhat, however, from the structure described by Warwicker.

Sincerely yours,

Linus Pauling:W