Compressed Air; O, Poisoning 733 



Blood A (natural respiration) 2 19.0; C0 2 42.0 



Blood B (tracheal respiration, copious bleeding) . . 2 13.1; C0 2 13.2 



Experiment CCXCVII. May 24, 1874. Experiment made before the 

 committee of the Academy of Sciences. 



Female dog of moderate size. Tube in the trachea. Oxygen bag. 



Compression taken to 7 atmospheres. At that time (5:30), I draw 

 35 cc. of carotid blood, from which some free gases escape. This 

 blood contains 33.2 cc. of oxygen per 100 cc. of blood, 76 of carbonic 

 acid, and 6.6 of nitrogen. 



Sudden decompression at 5:35; the animal has no convulsions. 

 A quarter of an hour afterwards, they occur in fits, and can be pro- 

 duced; at certain moments, the dog becomes as stiff as wood. 



She is chloroformed; the convulsions cease, but reappear when 

 consciousness returns. At 6:30, lying on her side, constantly makes 

 the movements of walking with her two front feet. 



At 7:30, rigidity again. 



The next day, at noon, this rigidity persists. The animal has re- 

 mained all night lying on the ground, without having moved from 

 the spot. The eye lacks sensitivity, the pupil does not react to light; 

 the rectal temperature is 23°, that of the room being 19°. 



The dog dies during the day. 



I hope that the reader will not object to this long series of 

 descriptions. The symptoms which I am studying at present 

 seemed to me so important that it was necessary to give many 

 examples in detail. The questions which present themselves are 

 numerous. We are now well enough informed to settle almost all 

 of them. 



But first, according to our custom, we should draw up a table 

 (Table XV) which summarizes the principal results of the data 

 which we have just reported. I listed the experiments according 

 to the increasing oxygen tension, expressed in Column 4 by its 

 real value, and in Column 5 by the equivalent in atmospheres. 



We are now ready to make a complete description of the fatal 

 effects of oxygen, to describe its symptoms, and even to analyze 

 the mechanism of the poisoning. 



Let us first discuss the concentrations. 



The convulsive symptoms, as Columns 5 and 10 of the table 

 show us, did not appear clearly until about 19 atmospheres. Dogs, 

 then, seem a little less sensitive than birds, upon comparing this 

 result with that in Table XIV. That would not be surprising, 

 but I do not hesitate to say that on this point my experiments do 

 not furnish sufficiently definite information. 



I can only say that the duration of the compression has much 

 to do with the intensity of the symptoms of oxygen poisoning. 



