Penicillin

By SIR ALEXANDER FLEMING, F.R.C.S., F.R.C.P., F.R.S. from the Inoculation Department, St. Mary's Hospital I HAVE in the last few years received a certain number of honours, but none has touched me more than the invitation to deliver the Robert Campbell Oration for thtis year in Belfast. I did not know Robert Campbell personally, but I have read much about him and have appreciated my great misfortune in not having come uitder his personal influence. It has been my pleasure, however, to have known for a considerable time many of his colleagues and pupils, in Belfast, and I have the greatest respect for their judgment, so when I have read what they have written ahbout Robert Campbell I know that he was one of the great ones taken away long bc fore he had finished his work. Still his memory remains, and that is perhaps the gi eatest thing that can happen to any of us. I have chosen as the subject of my Iatdress "Penicillin," not only because of its topical interest but because it is a subject which would have been dear to Robert Campbell, a thoughtful and progressive surgeon who loathed sepsis. Before, however,. I say anything about p)-nicillin I want to make allusion to. some of the work which led up to the 1)(Pssibility of my noticing a certain happening which proved to be the beginning of penicillin. The first event of importance was the coming of Almroth Wright (a Belfast man) ic St. Mary's Hospital when I wvas a student. He was just beginning vaccine 1therapy and the opsonic index had appeared shortly before I qualified. As soon s I qualified I went into the laboratory (and incidentally I have stayed there ever ;ince). Then for years I worked chiefly at phagocytosis, so I could never forget Ilhe importance of the leucocyte or of the body's natural defences. Next, Ehrlich introduced Salvarsan, and sent some over to St. Mary's. It was i:iy good fortune to use it, and the extraordinarily dramatic effect it had on syphilitic lesions made an enormous impression on one who for years had been accustomed to the slower and more leisurely effect of vaccine therapy on septic and other conditions. It showed what happened when the right chemical was introduced into the right patient with the right infection. Then during the last war I went to France with my chief, now Sir Almroth, and we settled down to study septic wounds and the action of antiseptics, in association %vith my good friend Professor W. W. D. Thomson. Ever since then I have been partial to work on antiseptics, but other things had to be done, and this was mnerely a side issue. Then in 1922 I happened on a very interesting and powerful naturally occurring antibacterial ferment which I called lysozyme. This occurred in almost all cells of the body and some of the secretions, especially those of the lachrymal gland and the respiratory tract. There again I was associated with Belfast in the person