Tributes 



the whole audience wanted to be amused — and they were intensely 

 amused at the stories which poured out. Sir Archibald at times seemed 

 to think it was perhaps a little too much and then immediately after- 

 wards there would be another story which set the whole room shaking, 

 and I felt Garrod's shoulders shaking next to me ! 



I am afraid that these are only reminiscences. It is a little difficult to 

 select things to say about someone of whom one has been so very fond. 



G. S. Adair 



I have been asked to deal with Sir Joseph Barcroft's work on the oxygen 

 dissociation curve, the expression of the degree of oxygenation of 

 haemoglobin in equilibrium with gas mixtures containing known pro- 

 portions of oxygen. This curve has been of fundamental importance 

 in physiological and physicochemical investigations of haemoglobin, 

 and recent work on methaemoglobinaemia has indicated one of its 

 clinical applications. 



This subject, the oxygen dissociation curve, provides a good example 

 of Sir Joseph's quite remarkable talents as a writer as well as a research 

 worker. His publications record new and important advances and at 

 the same time convey a most vivid impression of the progress of the 

 work. 



Sir Joseph's first work on the dissociation curve was partly inspired 

 by his interest in the oxygen tension in the blood in the capillaries. At 

 that time Professor Krogh's direct determinations of the oxygen tension 

 of blood were not published, and both Bohr in Copenhagen and Haldane 

 at Oxford had concluded that oxygen was secreted into the blood in the 

 lung capillaries. If the shape of the oxygen dissociation curve is 

 accurately known, and if it can be assumed that the percentage oxygen- 

 ation is a known function of oxygen tension, it should be possible to 

 calculate the oxygen tension of blood from measurements of oxygen 

 content and oxygen capacity, but when Sir Joseph began this work, 

 the shape of the dissociation curve was uncertain, and, as he states in 

 the first edition of his book The Respiratory Function of the Blood, 

 * Zuntz and Loewy had made the important observation that apparently 

 no two samples of blood, whether from man or beast, could be relied 

 upon to have the same dissociation curve.' 



Much of the earlier work on the dissociation curve of blood had 

 been hampered because the methods were elaborate and time- 



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