Copy letter from Leonard Colebrook to Sir Almroth Wright Typescript copy of letter from Colebrook to Wright written from the Burns Unit, Birmingham. Colebrook discusses his disagreement with Wright on the topic of immunization. Colebrook discusses the washed lath experiment, the experiment of the agar "clocks" showing immunization in vitro, and immunization in vitro as a practical guide to vaccine therapy, and goes into detail on these topics and why he disagrees with Wright. Colebrook also mentions Fleming and states that Fleming also finds some of Wright's findings difficult to believe. A later notes by Colebrook states that this is 'a very important letter'. 12 July 1944