Titles
- Letter from H. B. Zimmermann to Clarence Dennis1
- Letter from H. H. Dale to Alan Gregg1
- Letter from Harvey Cushing to Alan Gregg1
- Letter from Helen Keller to Florence R. Sabin1
- Letter from Hugh S. Taylor, Princeton University to Michael Heidelberger1
- Letter from K. Starr Chester, Rockefeller Institute for Medical Research to Michael Heidelberger1
- Letter from Leonard Colebrook to Alan Gregg1
- Letter from Lewis Hackett to Fred L. Soper1
- Letter from Linus Pauling to H. D. Springall1
- Letter from Linus Pauling to Professor Noyes1
- Letter from Lloyd H. Ziegler to Lawrence Kolb1
- Letter from Marjory Stephenson to Walter Fletcher1
- Letter from Max Delbruck, California Institute of Technology to Michael Heidelberger1
- Letter from Michael E. DeBakey and William H. Gillentine to MacGregor Instrument Company1
- Letter from Michael E. DeBakey and William H. Gillentine to O. O. R. Schwidetzky1
- Letter from Michael E. DeBakey to his parents1
- Letter from Numa P. G. Adams to Charles R. Drew1
- Letter from Oswald T. Avery to Fred E. Wright, National Academy of Sciences1
- Letter from Oswald T. Avery to Michael Heidelberger1
- Letter from Oswald T. Avery to Roy Avery1