Tributes 



evidence is cogent enough ', and so I bearded him on the stone stairs 

 outside the lab. His response was instant : ' Yes, that's a valid point. 

 Now will you join me as my colleague and set me back on the rails 

 again ? ' Of course I jumped at this chance, and it had a great effect 

 on my subsequent work, for it turned out to be one of the main factors 

 which led me later into partnership with Hartridge and thus opened 

 up our work on the measurement of the rate of very rapid reactions of 

 haemoglobin with oxygen and carbon monoxide and to all sorts of 

 other things. The point on which Barcroft and I had met opened up 

 for him the problem of measuring the output of the heart per minute, 

 and probably also the total volume of blood in the body. Two years 

 later, in 1922, we find him setting out to the Andes at the head of an 

 Anglo-American High Altitude Expedition, and on his way out there 

 by boat he made an observation which was to have a great effect on his 

 subsequent work. In practising up the blood volume method, he found 

 there was a marked increase when the ship got into warmer weather, 

 and he thought the increase too rapid to be explained by manufacture 

 of new blood, but must have come about through the mobilization of 

 blood, already existing, but in stagnant parts of the circulation. This 

 led him, after the expedition was over, to his work on blood reservoirs 

 — specially the spleen to begin with, but also the liver, skin and last 

 and most important the uterus. For it was the contact in this connec- 

 tion with this last organ, I think, that brought him to the main 

 scientific interest of his last fifteen years, foetal physiology. There is 

 no time, nor would I be competent, to speak here of his great pioneering 

 work in this field. Cambridge, a year ago, heard in this room a fine 

 lecture on this part of his life work, by his enthusiastic partner in it, 

 Dr. Donald H. Barron, now Professor at Yale University. Absorbed 

 though he was in the physiology of the mother and foetus, particularly 

 in regard to the differences in their haemoglobins, he never lost, or 

 even abated in the slightest degree, his interest in the other problems of 

 haemoglobin and of blood, whether old or new. He was always eager 

 to hear and talk about them, and the only times I can think of in 

 which he did not like to be interrupted were, either if he was in the 

 middle of one of his hectic experiments when he was usually working 

 flat out, or if he was on the way to catch a train, or on the way home 

 to lunch with Lady Barcroft. At any other time he nearly always seemed 

 to have most of the time in the world available, perhaps because he 

 had, as a rule, already done much of his day's work early in the morning, 

 before he ever got down to the laboratory, a salutary practice in which 

 I believe Professor Krogh also indulges. 



As illustrations of his abiding interest in older problems, I remember 

 two remarks. First, a few months before his death he said to me : 



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