490 Royal Society : — 



composition of the air enclosed along with blood, saturated as the 

 blood already was with oxygen, could not have happened. 



After having ascertained that air underwent certain changes in 

 composition during its contact with blood, it next became an object 

 to discover by which of the constituents of the blood these changes 

 were induced' With this view the author successively subjected the 

 organic compounds of the blood separately to the action of air, by 

 a similar process to that adopted in the case of the blood itself. 



A certain quantity of fresh fibrine, moistened with water, was satu- 

 rated with oxygen, placed in a receiver along with eight volumes of 

 air, and kept during twenty-four hours at a temperature of from 

 20° to 25° Cent. At the expiration of this time the gas on analysis 

 was found to have the following composition : — 



CaSc'acid : : : : n-i;} ^^^^^ oxygen=17'98 

 Nitrogen 82-02 



100-00 



thus showing that fibrine takes up a certain quantity of oxygen, and 

 gives off a stated amount of carbon combined with oxygen in form 

 of carbonic acid gas. 



The next experiments were made upon albumen, but as that sub- 

 stance could not be obtained in a pure, and at the same time un- 

 coagulated state from blood, the albumen of the hen's egg was 

 employed, which possesses very similar characters. It was found 

 that when a certain quantity of the white of the hen's egg was well 

 saturated with oxygen, and afterwards kept in contact with an equal 

 volume of air during a certain number of hours at a temperature of 

 36° Cent., the gas on analysis gave in 100 parts, — 



Oxygen 17*05 



Carbonic acid 209 



Nitrogen 80-86 



10000 



proving, in common with the experiments on the blood and on 

 fibrine, that albumen also possesses the property of absorbing oxygen 

 and disengaging carbonic acid. 



Some comparative experiments were also made upon serum and 

 upon blood-coagulum, in which it was found that the air confined 

 along with the serum yielded on analysis — 



Oxygen 16*74 



Carbonic acid 2-30 



Nitrogen 80-96 



100-00 



