Preparation of Heparin and Its Use in the First Clinical Cases

M ANY OF UJ8, who were friends of the late Dr. Jay McLean, had looked forward with great pleasure to seeing him again at this tiune and to discussing the problems wlhich occupied so much of his attention. We all join Dr.. Wright in paying tribute to Dr. MlcLean, the discoverer of heparin, and to Professor W. H. Howell and his colleagues, who extended this work and focused our attention oIn many of the most important prob-lenis in this field. A number of years ago Dr. McLean wrote to me and asked if we would take the responsibility for his collection of notes and reprints and other documents relating , to heparinr. I was honoured and extremely 1leased to accept this invitation. It is almost always true that a very careful search of the literature will reveal papers which anticipate, to varying degrees, the discovery of a signal advance ill medical or other sciences. In 1912, Doyon' published a paper in which he describes anl attempt to isolate and characterize ail anticoagulant released by the injection of peptone in a dog. This work was interrupted by World War I. There are a number of other intriguing findings in the literature, for example that of Schmidt2 in 1892, but their significance could only be appreciated after the discovery of heparin by wrote me a long, letter describing the whole history of his work on heparin, and a great deal about his subsequent researches. I will quote parts of this letter. Pharmacology, and is now Vice-President of the University for the Medical Sciences. These talks were not published although the secretary may have a record in the minutes of the Society. .. Concerning the lack of articles on heparin in the literature by me, you may be interested in the following. When I wrote the paper on "The thromboplastic action of cephalin," Doctor Howell did not think that I should include anything about the discovery of the anticoagulant. He felt that this should be studied more thoroughly and a paper written about it later. I argued, however, that I had made this finding during that academic year's work in 1915-1916, and felt that it should be included as a record of the work done during that period. I felt this the more strongly because I had already accepted a Fellowship in the Depart-iuent of Research Medicine at the University of Pennsylvania under …