Letter from David L. Edsall, Harvard University Medical School, Biston 17, Massachusetts, to Joseph Barcroft, Physiological Laboratory, Cambridge University He has been giving a lot of thought to the proposed expedition to Peru. At first he thought that it would be impossible on the grounds of cost and doubted that Bock and Redfield could be away during winter. He thought it might become possible if free arrangements could be made with mining and steamship companies. Now, he does not believe the idea is feasible and if an expedition is contemplated, it should be a shorter one to Monte Rosa, to arrange for a later and more extensive Anglo-American expedition to Peru. The Vice-President of the Cerro de Pasco mining company has indicated that they did not have sufficient accommodation for their own people. He is remains ready to help Barcroft to carry out his plan. 23 May 1921