Letter from Norman Heatley, Merck and Co, Rahway, New Jersey to Howard Walter Florey, Oxford Has sent some of the dry cellulose acetate phthalate - Rake reluctant to send any penicillin until he knew if the capsules were efficient - Squibb have sent some penicillin - Florey's fears that Merck will not send until experimental work completed are without foundation - does not know how Merck-Squibb collaboration is going - discusses extraction apparatus - mentions Coghill's extraction method - Continued 1 January 1942: comments on papers given at a meeting of the Society of American Bacteriologists - paper from Dawson and Co claimed crystalline penicillin - gives details - appears to be acid-form penicillin - wants details about Florey's purest material. 28 December 1941