26 



Dr. C. Bolton. Physiological Action of a [Mar. 20, 



The next day the animal seemed rather weak but otherwise normal. On 

 this day another dose of 1/20 gramme was given intravenously. The same 

 symptoms supervened and rapidly a general weakness appeared. Inspiratory 

 dyspnoea was succeeded by rapid breathing and the animal died a quarter of 

 an hour after the injection. Two spasms and fibrillary twitchings of the 

 muscles occurred before death. 



Post-mortem. — The heart was dilated, the cavity of the left ventricle being 

 globular. The urine in the bladder contained albumen. The medulla and 

 cervical and lumbar enlargements of the spinal cord were hardened, cut and 

 stained by Nissl's method. No abnormal cells were to be seen. 



Experiment 9. — Eabbit, weight 2125 grammes. Intravenous injection of 

 1/40 gramme of the filtered solution (= 0-011 gramme per kilogramme). 

 In a quarter of an hour the animal was seized with an attack of inspiratory 

 dyspnoea, but soon recovered from this and showed no further symptoms. 

 The next day 1/16 gramme (= - 029 gramme per kilogramme) was injected 

 into a vein. In three minutes the movements of the mouth began and 

 inspiratory dyspnoea also. Eespiration, 30 per minute. Pulse 292 per 

 minute. The heart sounds were normal and on auscultation of the bases of 

 the lungs, air was heard to enter freely. Attacks of slow inspiratory 

 dyspnoea alternated with attacks of rapid breathing. The animal died in 

 two and a half hours after the injection. 



Post-mortem. — Heart dilated. No other lesion. 



Experiment 10. — Eabbit, weight 1350 grammes. Intravenous injection of 

 1/30 gramme of the filtered solution (= - 024 gramme per kilogramme). 

 The movements of the tongue and mouth began in one and a half minutes, 

 and one minute later inspiratory dyspnoea commenced. Several attacks of 

 inspiratory dyspnoea alternated with attacks of rapid breathing. No 

 muscular weakness was to be seen. In three hours from the injection the 

 animal had practically recovered. The next day 1/25 gramme (= - 029 

 gramme per kilogramme) was injected intravenously. The same symptoms 

 ensued and death occurred in 20 minutes after a few convulsive movements. 



Post-mortem. — Heart dilated. No other lesion. 



Experiment 11. — Eabbit, weight 1700 grammes. Intravenous injection of 

 1/30 gramme of the filtered solution (= - 019 gramme per kilogramme). 

 In three minutes inspiratory dyspnoea commenced. On auscultation air was 

 found to enter the lungs all right. The heart was very irregular and 74 per 

 minute in frequency. The irregularity seemed to affect both force and 

 rhythm, the beats tended to occur in groups of threes and fives. 



In about eight minutes the heart became regular, and 148 per minute in 

 frequency ; the respirations were 142 per minute, and the inspiratory 



