Death in Closed Vessels 549 



520 grams lived 2 hours 20 minutes in 4.76 liters of air at 76 cm.; 

 which makes 17 minutes, per 1000 grams and per liter of air at 76 cm. 

 Lethal air: O* 5.4; CO2 15.7. 



CO2 



CO, _|_ 02 = 21.1 ; =1.01. Oxygen tension = 2.2. 



O2 



LXXXI. Weight 620 grams. Bell- jar of 19 liters. 



Began at 2:40; at 2:49 the pressure is 19.5 cm.; the animal stag- 

 gers. Cocks closed. 



At 2:55, falls; at 3:20, a little better; at 4:15, still making efforts 

 to rise; at 5:10, convulsive jerks; dies at 5:30; 20 minutes after, the 

 rectal temperature is 23°. 



Lived 2 hours 40 minutes in 4.71 liters of air; which gives 21 

 minutes, per 1000 grams and per liter at normal pressure. 



Lethal air: O* 8.1; CO2 15.6. 



CO2 



CO + 02 = 23.7; = 1.21. Oxygen tension = 2.0. 



O2 



The value of the oxygen tension in these different experiments 

 was: 



At normal pressure, 2.3; at 46.5 cm., 2.1; at 41.3 cm., 2.2; at 

 27.8 cm., 2.0; at 19.5 cm., 2.0; at 16 cm., 3.0; at 13.6 cm., 3.4; at 

 12 cm., 3.0. 



It will be noted that at very low pressures the sum C0 2 + 2 

 was: 21.1; 21.4; 22.1; 22.1; 23.7; and 24.3, that is, higher than the 

 original proportion of oxygen. The excess is due, no doubt, to the 

 carbonic acid contained in the intestines of these rodents, whose 

 bellies balloon out at the beginning of very low pressures, and 

 which probably then let escape a part of their expanded gases. 



As to the duration of life, reducing it to 1000 grams of body 

 weight, it was, per liter, : at normal pressure, 12 minutes; at 

 46.5 cm., 14 minutes; at 41.3 cm., 24 minutes; at 27.8 cm., 17 minutes; 

 at 19.5 cm., 21 minutes; at 16 cm., 16 minutes; at 13.6 cm. and at 

 12 cm., death came much more rapidly. We find here a regularity 

 not displayed by the birds, which were extremely variable in their 

 behavior under the bell-jars. The two extremes 12 and 24 are 

 explained by the incessant movement or the complete calm of the 

 experimental animals. 



If we compare these numbers with those furnished us by the 

 other mammals, we see that they are about double those given by 

 adult cats/about equal those of rabbits, and much lower than those 

 of new-born kittens. Let us say in conclusion that for sparrows, 

 whose ordinary weight is about 30 grams, making the same calcula- 



