710 Experiments 



method of physiologists, I had to set aside for the moment the 

 effects of low concentrations of oxygen, which are hard to esti- 

 mate, and study first the violent symptoms caused by high concen- 

 trations. In the first place, I investigated the action of oxygen 

 under high tension, generally adding to the manometric pressure 

 a percentage of oxygen sufficient to produce a value much greater 

 than that in the air which we breathe. 



I think it advisable to report here a certain number of experi- 

 ments which will permit me to give first a description of the symp- 

 toms resulting from what I shall call, if only for convenience in 

 nomenclature, poisoning by oxygen. 



Already we have noted the convulsions which had attacked 

 sparrows subjected to this dangerous agent. The following ex- 

 periments, almost all performed in the Seltzer water apparatus, 

 will furnish us new examples. 



Experiment CCLVIIK January 29. House sparrow subjected to 6 

 atmospheres, 5 of which were oxygen, from 3:50 to 3:58. The mix- 

 ture contained 81 per cent of oxygen, and the tension of this gas was 



486 



therefore equivalent to 81 x 6 = 486, which corresponds to = 23.2 



atmospheres of air. 20.9 



At 4:03, violent convulsions, the head hanging down; whirling. 



I lower the pressure and bring it to 3.5 atmospheres. During the 

 decompression, new convulsions. 



Immediately after, third attack; then new attacks, weaker and 

 weaker, at 4:06, 4:11, 4:14. 



During the attacks, and in the intervals, the respirations are very 

 deep and very hasty; the beak is wide open. 



The attacks come oftener at intervals of 1 to 2 minutes, becoming 

 weaker and weaker. They subside about 4:40; the bird remains lying 

 on its back, its respirations become rarer and rarer, and cease at 5 

 o'clock, without any other movement. 



At 5:10, the rectal temperature is 24°. 



Experiment CCLIX. February 2. House sparrow, subjected to 6 

 atmospheres, 5 of which are oxygen. The oxygen tension is about 450. 



After 5 minutes, strange tremors, a quivering through the whole 

 body; then it remains motionless, its beak down. 



After 10 minutes, an attack of strong convulsions; another at 12 

 minutes; a third, weaker, at 17 minutes. The bird is very sick, breathes 

 from 50 to 70 times a minute, its beak wide open. 



Brought back carefully to normal pressure; recovers a very little; 

 rectal temperature, 34° to 35°. In its cage it has new convulsive 

 attacks; at the end of a quarter of an hour, gets up on its feet; but 

 when it is threatened with the finger, it draws back walking on the 

 whole tarsus, and falls backwards. 



