March 31, 1924.
Dear Dr. Sabin:
I have your very gratifying letter of March 24 and I will present it, together with an outline of the plans we have discussed together, at the meeting of the Board of Scientific Directors of the Rockefeller Institute which comes on April 26 (not the 19th as I thought).  I shall be able to write you immediately after that meeting, telling you how the plans are received by our Board.  I feel that there is an excellent chance of getting forward with the diseases of the blood-forming organs.
I am pleased also with the possibility of Dr. Cunningham being interested in the plans to the extent that he would consider becoming part of the working group in New York.
From what you have told me, I do not feel that Dr. Doan is so essential.  If he craves clinical work immediately, I should hardly feel like persuading him to defer.  But you understand this situation far better than I do.  I cannot but believe, however, that you and Dr. Cunningham would soon train another young man with clinical interests to help as Dr. Doan is now doing.  If Dr. Doan would like to talk over plans with me (possibly also with Dr. Cole) after the Board meeting to which I referred, I should be happy to talk with him.  I may be coming to Baltimore within a week or two, and could talk with him then.
I need not say that I should feel it a great thing to have you at the Rockefeller Institute.
With warm regards,
Yours sincerely,
Simon Flexner
P.S.  Thank you very much for the photograph of the drawing of Dr. Mall.