Department of Physical Chemistry
Harvard Medical School
Boston, Massachusetts

May 19, 1922

Dr. John J. Macleod,
University of Toronto,
Toronto, Canada.

Dear Sir:

My interest in the subject of your communication to the New Haven meeting has been increased by the papers which have appeared in the Journal of Laboratory and Clinical medicine and the Journal of the Canadian Medical Association, and also by a recent conversation with Dr. Collip, whom I had the pleasure of meeting at this laboratory.

I understand that it is your intention to have the details of the preparation of the pancreatic extract published at an early date, and in the meantime you refuse to make known any data that might lead to any misuse of your pupils' discovery. While I can but respect your natural reserve, I hope that it will be possible for you to furnish me with some data that will enable me to make things ready so that when the whole thing is published I will be in a position to obtain the extract with as little delay as possible.

My reason for entertaining this hope is, aside from my great scientific interest in the problem and aside from the needs of the moderately severe cases of diabetes which I have treated, the fact that there is in Barcelona a diabetic patient of the most severe type who would have died, perhaps tow years ago, except for the extreme care taken in his treatment and for the great good will which he had shown in carring it out. Very often I have wondered how far I had the right to impose on him the terrible privation that are necessary to maintain a life which is the most miserable one that can be imagined. Of course, I have always felt that it was not only my right, but my duty to prolong his life as long as I could, not only for general ethical reasons, but also because of the possibility that the efforts of some of the diabetic researchers might prove successful while he was still alive. Now it seems that such is the case. You have in your hand something that can make worth while the past sufferings of this particular human being. He knows this, because Dr. Pi Suner, whom I told of your New Haven communication, has told him against my advice. This boy'' condition is such that it might well be a question of weeks, even of days, before it would be too late for him to be benefited by Insulin.

I do not presume to ask you to break your reserve by giving me the details f the process of your preparation. Of course, I would be exceedingly glad and grateful if you would, and will give you full assurance of my discretion. It is possible, however, that the process may involve either the use of apparatus that