438 



SPIRILLUM CHOLEILE ASIATICS. 



Infection of 

 mouth. 



Preparation 

 of the 

 animals 



Besults. 



control experiments shows at once that the operation 

 per se, when properly carried out, does not place the 

 animals in any serious danger. 



Koch has however attempted to avoid this operation, 

 which is by no means insignificant, and to obtain infec- 

 tion of guinea-pigs by the mouth, and he has succeeded 

 by neutralising the gastric juice in the first instance by 

 means of soda solution, and subsequently administering 

 substances which cause slowing of the peristaltic action, 

 and thus enable the comma bacilli to remain for a longer 

 time in the small intestine. The following is the mode 

 in which an experiment of this kind is performed. In 

 the first place 5 cc. of a 5 per cent, soda solution are 

 introduced into the stomach of the guinea-pigs by means 

 of a catheter passed downwards from the mouth (it has 

 been shown that as a result the intestinal contents have 

 an alkaline reaction for several hours), and some time 

 afterwards 10 ccm. of fluid, to which one or several drops 

 of a pure cultivation of comma bacilli have been added, 

 are introduced; if only a very little of the cultivation, 

 one-third of a drop or less, is employed the result is 

 uncertain. After the injection a dose of opium is ad- 

 ministered to the animals ; if the opium is introduced into 

 the stomach of guinea-pigs it scarcely produces any effect, 

 and hence it is better to inject it directly into the abdo- 

 minal cavity by means of a syringe, the dose being 1 ccm. 

 of tincture of opium to every 200 grammes of the body 

 weight ; the back of the animal is grasped with the left 

 hand in such a manner that the abdomen is projected 

 forwards, and then the syringe is rapidly pushed into 

 the middle of the abdominal wall ; when the operation is 

 performed in this manner the intestines are pushed to 

 one side so completely that they have almost never been 

 injured, nor have any other bad consequences been 

 observed. 



After the administration of the opium narcosis occurs, 

 lasting from to 1 hour, after which the animals seem 

 quite well. On the evening of the same day, or on the 

 following day, the animals lose their appetite and seem 

 ill; a paralytic weakness of the hinder extremities 



