152 Intelligence and Miscellaneous Articles. 



second ; then the animal was restored by air ; afterwards the gases 

 were extracted simultaneously. 



Carbonic 



Nitro- 





Carbonic 



acid. 



gen. 



Oxygen. 



oxide. 



100 cubic centimetres of the 1 .q.e 

 arterial blood first taken J 



1-57 



14-65 



4-28 



100 cubic centimetres of the 1 









arterial blood afterwards V 44*3 



2-78 



4-01 



18-41 



taken J 









Other experiments, made under the same conditions, give analo- 

 gous results. Hence we see that in an animal breathing air con- 

 taining -J^ of carbonic oxide (a mixture highly poisonous), the 

 arterial blood, between the 10th and 25th second, contains already 

 4 per cent, of carbonic oxide and less oxygen than the normal 

 blood (14*6 per cent.) ; and between 1 minute 15 seconds and 1 

 minute 30 seconds, 18*4 per cent, and oxygen in very diminished 

 quantity (4 per cent.). At that time the animal was in great dan- 

 ger ; and had the experiment lasted a minute longer, it would have 

 died. 



These indisputable results are directly applicable to man ; and we 

 may assert that if a man enters a highly deleterious atmosphere, 

 the gaseous poison is dissolved in the arterial blood from the first mi- 

 nute, and brought into contact with the anatomical elements, which 

 kills him. 



Every day we have too numerous examples of sudden death hap- 

 pening to workmen whose occupations compel them to expose them- 

 selves to deleterious gases or vapours, either in descending wells or 

 entering the galleries of mines, the air of which is poisoned, or more 

 or less deprived of oxygen. But physiologists have certainly given 

 advice which might in future free the life of man from all such dan- 

 gers ; and this advice ought to be carried out by law. 



Before descending a well, ditch, or gallery, of which the air has 

 not been renewed for a long time, the workman ought to lower a 

 cage containing a bird or a small mammal, as a rat or a guinea-pig : 

 if the animal, left in the confined atmosphere for ten to fifteen 

 minutes, can stand this test, a man may descend without fear ; if 

 the animal succumb, ventilation must be energetically established, 

 until another animal can resist a new proof. 



The employment of an animal in this manner would preserve man 

 from accidents too frequently mortal, as the Davy lamp, in coal- 

 mines, has saved the lives of so many miners. — Comptes Rendus, 

 May 30, 1870, 



