378 BACTERIOLOGY. 



neutralized by injecting through a soft catheter passed 

 down the oesophagus into the stomach 5 c.c. of a 5 per 

 cent, solution of sodium carbonate. Ten or fifteen min- 

 utes later this was to be followed by the injection into 

 the stomach (also through a soft catheter) of 10 c.c. of a 

 bouillon culture of the cholera spirillum. For the pur- 

 pose of arresting peristalsis and permitting the bac- 

 teria to remain in the stomach and upper part of the 

 duodenum for as long a time as possible, the animal was 

 to receive, immediately following the injection of the 

 culture, an intraperitoneal injection, by means of a 

 hypodermic syringe, of 1 c.c. of tincture of opium for 

 each 200 grammes of its body weight. Shortly after 

 this last injection a deep narcosis sets in and lasts from 

 a half to one hour, after which the animal is again as 

 lively as ever. Of 35 guinea-pigs inoculated in this 

 way by Koch, 30 died of a condition that was, in gen- 

 eral, very similar to that seen in Asiatic cholera. 



The condition of these animals before death is de- 

 scribed as follows : twenty-four hours after the opera- 

 tion the animal appears sick; there is a loss of appetite, 

 and the animal remains quiet in its cage. On the fol- 

 lowing day a paralytic condition of the hind extremities 

 appears, which, as the day goes on, becomes more pro- 

 nounced; the animal lies quite flat upon its abdomen or 

 on its side, with its legs extended; respiration is weak 

 and prolonged, and the pulsations of the heart are hardly 

 perceptible; the head and extremities are cold, and the 

 body temperature is frequently subnormal. 



The animal usually dies after remaining in this con- 

 dition for a few hours. 



At autopsy the small intestine is found to be deeply 

 injected and filled with a flocculent, colorless fluid. The 



