OF THE BRAIN, ETC. 25 



The next order of experiments was instituted 

 for the purpose of ascertaining the quantity of air 

 consumed by animals in which the circulation of 

 the blood was kept up by means of artificial 

 respiration, after the brain had ceased to perform 

 its functions. 



EXPERIMENT IV. 



Thermometer 65, barometer not noted. 



Having procured two rabbits of the same size 

 and colour, I divided the spinal chord in the 

 upper part of the neck of one of them. An open- 

 ing was made in the trachea, and the lungs were 

 inflated at first by means of a small pair of bel- 

 lows. Two ligatures were passed round the 

 neck, one in the upper, and the other in the 

 lower part, behind the trachea. The ligatures 

 were drawn tight, including every thing but the 

 trachea ; and the nerves, vessels, and other soft 

 parts between them were divided with a bistoury. 

 Eight minutes after the division of the spinal 

 chord, the thermometer in the rectum had 

 sunk to 97. The animal was placed under a 

 bell-glass, and the lungs were inflated by pressing 

 on the gum-bottle about 50 times in a minute. 

 When this process had been continued for 30 

 minutes, a portion of air was abstracted from 

 the bell-glass, and preserved for examination. 

 The heart was found acting regularly, but slowly, 

 the thermometer in the rectum had fallen to 90. 



The second rabbit was killed by dividing the 

 spinal chord about the same time when the 



