Oil Sal Nitrum and Nitro- Aerial Spirit 75 



and there, through the whole mass of the lungs. And 

 yet in the lungs, when boiled and dissected, an almost 

 infinite number of openings resembling most minute 

 points are seen by the aid of the microscope. But 

 whether these points are the mouths of capillary 

 tracheae, or of vessels opening into the blood, I cannot 

 state with certainty. 



Hence it is manifest that air is deprived of its elastic 

 force by the breathing of animals very much in the 

 sam.e way as by the burning of flame. And indeed 

 we must believe that animals and fire draw particles 

 of the same kind from the air, as is further confirmed 

 by the following experiment. 



For let any animal be enclosed in a glass vessel along 

 with a lamp so that the entrance of air from without 

 is prevented, which is easily done if the orifice of the 

 inverted glass be immersed in water in the manner 

 already described. When this is done we shall soon 

 see the lamp go out and the animal will not long 

 survive the fatal torch. For I have ascertained by 

 experiment that an animal enclosed in a glass vessel 

 along with a lamp will not breathe much longer than 

 half the time it would otherwise have lived. 



Nor is there any reason for supposing that the 

 animal is suffocated by the smoke of the lamp, for 

 scarcely any smoke will emanate from it if spirit of 

 wine is used, and indeed the animal will live in the 

 glass for some time after the extinction of the lamp — 

 that is, after the fumes have entirely disappeared — so 

 that it is by no means to be supposed that it has been 

 suffocated by the fumes of the lamp. But since the 

 air enclosed in the glass is in part deprived of its nitro- 

 aerial particles by the burning of the lamp, as has 

 already been pointed out, it cannot support long the 

 breathing of the animal, hence not only the lamp but 



