Typescript letter written on Marine Biological Laboratory, Woods Hole, Massachusetts letterhead signed by G. H. A. Clowes. Autograph additions in top left corner of first page ask that 3 copies be made of the letter. Dr. Clowes assures Dr. Banting that Eli Lilly & Co. will supply him with enough insulin to make up for the loss of supply caused by a breakdown in the production of insulin at the Connaught Laboratories. Discusses the difficulties with the Toronto process of manufacturing insulin.