14 Effects of Oxygen and other Gases 



rabbit of about three weeks old was similarly immersed, and 

 in little more than a minute its heart appeared to act strongly, 

 and its breathing was hurried and laborious. It then reeled 

 and staggered, and with difficulty poised itself, finally resting 

 against the side of the glass in a state of stupor. The respira- 

 tions became weaker and slower, and the nostrils ceased to 

 move. In about two hours and a quarter the diaphragm was 

 perfectly inactive. The animal was then removed and opened, 

 when the pleura, lungs, and brain, were found highly injected 

 with thin florid blood. Another rabbit of the same brood was 

 immersed in the same gas from which the first was taken, and 

 it fell apparently dead in about two minutes. It was removed 

 and resuscitated in the open air. After these experiments a 

 lighted taper was extinguished in this gas. 



When the experiments with the nitrous-oxide are compared 

 with those conducted with oxygen gas, it is observable that the 

 results are ultimately very similar, but that the effects are much 

 sooner apparent, more urgent, and resemble rather those of 

 intoxication from alcohol. The combination of azote with 

 the oxygen in the nitrous-oxide seems to account for this dif- 

 ference, and the absorption of the oxygen may explain the 

 similarity of appearance upon dissection when the state of the 

 organs is compared with that derived from breathing pure 

 oxygen. The nitrous-oxide, like the oxygen, seems to bear 

 an affinity to poisonous substances in its effects, and is de- 

 structive to animal life when undiluted with atmospheric air. 



II. EXPERIMENTS WITH NITROGEN. 



Several sparrows were immersed in nitrogen gas, and fell 

 dead in about thirty seconds, having gasped and struggled im- 

 mediately on immersion. Some mice exhibited similar phe- 

 nomena. In all these animals the right ventricle of the heart 

 was found full and distended with dark blood, and the vessels 

 of the brain, pleura, and lungs, were collapsed. 



A frog was placed under a glass vessel of nitrogen, and 

 remained more than two hours unaffected, at the termination 

 of which period it began to gasp a little, and then appeared dull 

 and lethargic. Next morning it was found dead. The blood 

 was universally dark coloured. 



