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Chapter XVII 



this can be done. To some of Douglas's blood lactic acid was added 

 to the extent, in one case of about 0*037 per cent, in another 0*075, 

 the dissociation curves were then determined ; their similarity to 

 those shown in Fig. 122 is very striking. 



That these changes in the blood were due to simple oxygen want 

 was tested by trying to induce them in animals. In two cases a cat 



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FIG. 124. O Defibrinated cats' blood. Points from Cat I after partial occlusion of 

 trachea and 15 minutes breathing of gas of increasing poverty in oxygen. Cat II 

 at beginning of exp. O after 15 minutes gas-respiration, x after 21 minutes ditto. 

 The gas was becoming continually poorer in oxygen, at the end it was about 4/ oxygen. 



was subjected by Orbeli and myself to an atmosphere in which the 

 oxygen gradually got rarer and rarer as time went on. The curves 

 obtained are shown in Fig. 124. 



(2) We have said enough to indicate the possibility of a method 

 for the purpose of estimating the effective strength of the acid or 

 acids thrown into the blood apart from the carbonic acid. 



