INFECTIONS OF THE DIGESTIVE TRACT 249 



To reduce the oxidizing processes in the cells, animals 

 were poisoned with hydrocyanic acid, a substance which 

 possesses a high degree of power to depress the ability 

 of animal cells to take up oxygen from the blood. The 

 effect of dyspnoea from tracheotomized animals was 

 also investigated to some extent and similar observa- 

 tions were made upon the influence of chloroform given 

 to the point of narcosis upon the fate of indol. 



In general it may be said that rats, mice, guinea-pigs, 

 and dogs subjected to subcutaneous injections of potas- 

 sium cyanide too small in themselves to cause marked 

 symptoms, were later subjected to subcutaneous or peri- 

 toneal injections of indol or phenol in watery solution 

 or in oil. The symptoms observed in such cases were 

 compared with those obtained from the injection of 

 indol or phenol without any preceding treatment with 

 potassium cyanide. The result almost regularly ob- 

 served was that the convulsive twitching which is char- 

 acteristic of the action of the phenol and of indol was of 

 greater intensity and longer duration in the animals 

 subjected to potassium cyanide than in the case of the 

 control animals. For example, into a guinea-pig weigh- 

 ing 370 gm. was injected 0.0003 gm. of indol per gram 

 of body weight. The characteristic twitching came on 

 in eight minutes and lasted ninety-seven minutes. It 

 was mild in character. Into another guinea-pig, weigh- 

 ing 380 gm., 0.005 mg. of potassium cyanide per gram 

 of body weight was injected together with 0.0003 gm. 

 indol per gram of body weight. The twitching began 

 in two minutes, was much more violent than in the 



