Max 13, 1955

Professor T, Caspersson
Institute for Cell Research
Karolinska Institutet
Stockholm 60, Sweden

Dear Professor Caspersson:

I take this opportunity to complete my reply to your letter of
April 1, concerning Dr. George Klein, Earlier this week, I had the
pleasure of meeting him for the first time, and we spent the better
part of two days in detailed discussions of his work on ascites tumors,
which I had previously followed with avid interest through his publi-
cations, This meeting enables me to confirm what you already know, that
Dr. Kiein is certainly one of the most brilliant workers in this field,
and that his solid accomplishments already concluded are but a forerunner
of his continuing promise for the future.

Most impressive of Dr. Klein's talents, in my opinion, is his capacity
to make use of a wide range of scientific disciplines—- cytochemistry,
immunology, genetics-- as each is required for a given problen,

It would take too long to review, in any detail, Dr. Kiein's experi-
mental work; its overall excellence must be familiar to you. I found his
analysis of "The nature of mammalian lymphosarcoma transmission by isolated
chromatin fractions" especially appealing as a contribution to genetics,
and one that will surely set the pattern for proper experimental control
of claims of extracellular transmission of cancer.

In addition to his brilliant command of his own field, I found Dr.
Klein to be a stimulating person with whom to discuss my own work-- azain
I found much to admire in his intellectual flexibility, and aside fron
his direct contributions, I enwy your Institute the presence of so com-
petent a critic,

I hope you will not consider this an extravagant evaluation-- I can
assure you it is not lightly recorded, I believe, however, that I will not
be doybted in suggesting that Dr. Klein is among the most eminent scholars
in his scientific field in the world today.

With best regards

Yours sincerely,

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