Death in Closed Vessels 545 



CO* 



CO -j- O2 = 20.1; = 0.95. Oxygen tension = 2.2. 



O2 



LXVI. Bell- jar of 2.5 liters. 



Entered at 3 o'clock; at 3:06, pressure is 25.5 cm.; cocks closed; 

 dies at 5:40. 



Lethal air: O* 7.1; CO2 13.5. 



CO2 



CO + 02 = 20.6; = 0.98. Oxygen tension = 2.4. 



O2 



LXVII. Bell-jar of 3.2 liters. 



Entered at 2:54. At 3 o'clock, pressure 20.5 cm.; mews. Cocks 

 closed. Dies at 7:15. 



Lethal air: Oa 8.5; CO* 12.0. 



CO2 



CO* + 0* = 20.5; = 0.97. Oxygen tension = 2.2. 



O2 



LXVIII. Bell- jar of 5 liters. 



Entered at 2:38; at 2:48, pressure is 22 cm.; cat still walks and 

 mews; at 2:53, pressure is 16.2 cm.; animal is lying flat. Cocks closed. 

 At 3:08, pressure lowered to 13.4 cm. 



Dead at 7:35. 



Lethal air: O* 13; CO2 7. 



CO2 



CO^ + O- = 20.0; = 0.98. Oxygen tension = 2.2. 



O2 



O, x P 



The ratio is maintained here with remarkable regu- 



76 

 larity at 2.2, a number about half that given by adult cats. 



Already, in my Lessons (page 510), I had found that, while 

 adult cats leave on the average 5.3 per cent of oxygen in confined 

 air, when they die at normal pressure, new-born kittens left only 

 3.0 per cent. For adult rats, the average was 2.0 per cent, and for 

 a new-born rat, 0.75 per cent. 



If now we make the calculations necessary to find the duration 

 of life of these new-born kittens, reduced to a liter of air at 76 cm. 

 and to a kilogram of body weight, as we did for the adults, we find 

 that this duration is: at 58 cm., 33 minutes; at 25.5 cm., 24 minutes; 

 at 20.5 cm., 37 minutes; at 13.4 cm., 32 minutes. 



We see that the duration of life was obviously the same at very 

 low pressures as at average pressures. Moreover, comparing these 

 figures with those obtained from the study of adult cats, we see 



