CHLOROFORM A POISON 



23 



and this seems to be the general experience. The sufferer from 

 emphysema should experience the same difficulty in getting 

 chloroform as he does in getting oxygen. 



Something has already been said as to the result of alteration 

 of rate of respirations on the absorption of chloroform. The 

 following experiment by the writer may throw some light on 

 this matter. A cat, two kittens, a guinea-pig, a rabbit, a rat and 

 a mouse were placed in a closed glass box, into which a 2 per 

 cent, vapour of chloroform was pumped. The animals were 

 carefully watched, and the time of death in each case noted. 

 Below is given a table showing the results obtained : 



It will be observed that although the animals were inhaling 

 exactly the same concentration of chloroform, the periods which 

 elapsed before their deaths varied very widely. At first sight, then, 

 it would seem that a genuine idiosyncrasy — that is, an idiosyn- 

 crasy depending on a special susceptibility to the chloroform 

 which reaches the tissues by the lymph — exists in some members 

 of the animal kingdom. But a more careful scrutiny of this 

 experiment does not support such a conclusion. Although the 

 animals all inspired the same concentration of chloroform, the 

 rate of their respirations showed very marked differences. It has 

 already been pointed out that the rate of chloroform absorption 

 varies directly as the rate of respirations ; one would, accord- 

 ingly, expect that the fastest-breathing animal would die first : 

 this is exactly what occurred. The animal which died first was 

 the mouse, and this animal was breathing much more rapidly 

 than any of the others. Unfortunately the rate of respirations 

 of the various animals was not recorded numerically, since it 

 was the experiment itself that suggested that the relative rapidity 

 of respiration was an important consideration. 



The following rates of normal respiration are taken from 



