April 3, 1940
Dear Professor Heidelberger:
I am looking forward keenly to seeing you in New York, some time between April 12 and 17. My wife and I are interested in the theater, and our evenings may be pretty well filled by going to plays, provided that we get tickets.  Would you be free during the day some time in this time so that I could come and talk at length with you about serology?  We are leaving on Sunday but an air mail letter mailed on Thursday should reach me, or a 1etter may be addressed to me at the Commodore Hotel, New York City.
Since talking with you at the Mirsky's I have written out a rough account of my ideas on the structure and formation of antibodies, and have made a number of predictions on the basis of the theory.  I told Dr. Sabin and Landsteiner about them when in New York in March, but since I was in town only from Saturday morning at 9 until Sunday at 5 I did not have a chance to come to see you.  Please let me know what time would be most suitable to you for me to visit you.
Sincerely yours,
Linus Pauling