INOCULATION INTO THE SEROUS CAVITIES. I93 



The operation is one that cannot be learned from 

 verbal description. It can only be successfully per- 

 formed after actual practice. 



If the precautions which have been mentioned are 

 observed, but little difficulty in performing the opera- 

 tion will be experienced. 



Its convenience and simplicity over other methods for 

 the introduction of substances into the circulation com- 

 mend it as an operation with which to make oneself 

 familiar. The animals sustain practically no wound, 

 they experience no pain — at least they give no evidence 

 of pain — and no anaesthesia is required. 



INOCULATION INTO THE GREAT SEEOUS CAVITIES. 



Inoculation into the peritoneum presents no difficulties 

 if fluids are to be introduced. In this case one makes, 

 with a pair of hot scissors, a small nick through the 

 skin down to the underlying fasciae, and, taking up a 

 fold of the abdominal wall between the fingers, plunges 

 the hypodermatic needle through the opening just made 

 directly into the peritoneal cavity. There is no fear 

 of penetrating the intestines or other internal viscera if 

 the puncture is made along the median line at about 

 midway between the end of the sternum and the sym- 

 physis pubis. Though this may seem a rude method, it 

 is, nevertheless, the rarest of accidents to find that the 

 intestines have been penetrated. The object of the 

 primary incision is to lessen the chances of contaminat- 

 ing the inoculation by bacteria located in the skin, 

 some of which would adhere to the needle if it were 

 jilunged directly through the skin, and might complicate 

 the results. 



