Compressed Air; 2 Poisoning 715 



although the temperature had fallen to 32° in less than a half- 

 hour, it rose rather quickly to nearly 40° and the bird survived. 



I shall later dwell upon this remarkable fact, to which at present 

 I merely call attention; it shows very clearly that the symptoms 

 of oxygen poisoning are not due to an exaggerated activity im- 

 parted to the intra-organic combustions. 



The first idea which would come to mind, and I admit freely 

 that it came to mine immediately, is that under the influence of 

 this super-saturation of oxygen the animal tissues would be con- 

 sumed excessively, that an increase in the temperature would re- 

 sult, and that the convulsions which appeared could be compared 

 to those which precede the death of animals over-heated in a 

 drying-oven. Now we can state immediately that this is not true, 

 although later I shall analyze this important phenomenon thor- 

 oughly. 



Finally I shall say a few words of a symptom always present 

 in birds in cases of oxygen poisoning, a symptom which I have 

 designated by the expression "bloody suffusions of the cranium." 

 They are hemorrhages which fill the cranial diploe; in the 

 mildest cases they consist only of very small dots; these dots 

 are replaced by wide spots which become confluent in severe 

 cases, and the spongy tissue of the bone fills with blood. They 

 always begin in the occipital, but may affect the whole cranium. 

 They appear before the convulsions, and when the bird does not 

 die, they are not absorbed for several weeks. Although they 

 always exist when the symptoms due to oxygen become serious, 

 they are not especially characteristic of this poisoning. Since my 

 attention was called to their existence, I have found them quite 

 often in asphyxia and death by decompression. In fact, they were 

 noted in some of the experiments reported in Chapter I; when 

 they are not mentioned, it simply means that no one looked for 

 them. I should add that I never saw them so extensive or so deep 

 as in oxygen poisoning. I have no understanding of their mech- 

 anism; they appear without any convulsive phenomenon, and 

 autopsies have not shown any apoplexies in any other part of the 

 body. 



Let us now analyze a little more deeply the phenomena just 

 described. Upon what anatomical element does excessive oxygen 

 act? What is the cause of the convulsions? Is the heart directly 

 attacked, as it is by such a great number of poisons? The data 

 which have just been reported would be insufficient to permit 

 us to reply completely to these different questions. 



