Typescript letter written on Marine Biological Laboratory, Woods Hole, Massachusetts letterhead with a manuscript postscript and corrections made in ink. The letter is signed by G. H. A. Clowes. Dr. Clowes addresses the question of the volume of insulin produced by Eli Lilly & Co. and the amount required by Dr. Banting. Clowes indicates that Eli Lilly & Co. will be unable to supply other clinics with insulin unless Banting cuts back on the amount of insulin he uses. Part of Clowes' postscript reads: 'So you see I can protect you and you can help me best just now by wiring Mr. Lilly an indication that we can start experiments again.'