EXFERIlfENTAL INOCULATION. 315 



found, however, the following to be the most efficacious 

 procedure. 



.5 c.c. of a bouillon typhoid culture twenty-four hours old was in- 

 jected subcutaneously into a guinea-pig, and at the same time 10 to 

 12 c.c. of sterilised old culture of B. coli were introduced into the 

 peritoneal cavity. The animal died in from twelve to fourteen hours with 

 typhoid bacilli in the peritoneum and a few in the blood and organs. 

 From the former situation bouillon cultures were made and used for 

 the subcutaneous injection of a second animal, which also received 

 intraperitoneally some sterilised B. coli culture, a less quantity of the 

 latter being now found sufficient to cause death in the same time. In 

 a series of animals thus inoculated, each from the previous member, 

 less and less B. coli culture was found sufficient until this could be 

 dispensed with altogether, the typhoid bacilli alone being sufficient. 

 After about thirty such passages a culture of a typhoid bacillus of 

 exalted virulence was obtained. 



The intraperitoneal injection of a few drops of such 

 a culture of highly-exalted virulence, or the subcutaneous 

 injection of 3 to 4 c.c., caused in guinea-pigs and rabbits 

 illness and death in from twelve to twenty -four hours. 

 After injection the temperature first rose and then gradually 

 sank till death, and there were flatulence and abdominal 

 tenderness. Post mortem the spleen was enlarged and 

 haemorrhagic, the liver enlarged and fatty, the kidneys 

 congested, whilst the intestine showed congestion, with 

 excess of mucous secretion and swelling of the lymphoid 

 patches. There was desquamation of the intestinal epithe- 

 lium. The Peyer's patches were enormously infiltrated, 

 sometimes almost purulent, and, where the inocula- 

 tion had been intraperitoneal, they contained typhoid 

 bacilli. These were also found in the mesenteric lym- 

 phatics and glands, and in the spleen, where they occurred 

 in groups in the pulp but not in the Malpighian bodies. 

 Sanarelli insists that by whatever path the bacilli were 

 introduced into the body the brunt of the pathological 

 effects always fell on the intestine and abdominal organs ; 

 and with regard to the bacilli themselves, though they 

 might be found in the blood, their usual site was in the 

 solid organs, especially the spleen. Pfeiffer, criticising 



