198 BACTERIA. 



which it has gained access. This bacillus, then, has been 

 found in the body ; it has also been found by Pfeiffer in the 

 dejecta of typhoid patients, and now it has been found in the 

 water supply, so that the chain of evidence is, so far, pretty 

 conclusive. It is a somewhat important fact that the typhoid 

 bacilli may remain active for a considerable length of time 

 in the stools, for the bacilli in faeces kept in a sterilized 

 tube for fifteen days remain alive at the end of that period, 

 and vigorous cultivations could be made from such material. 

 Experimenters were now confronted with the difficulty that 

 typhoid fever is seldom met with except in the human subject. 

 Experiments were made on animals by injecting cultures of 

 the typhoid bacillus into the aural vein of rabbits, with the 

 result that about 50 per cent, of the animals died, and on 

 post-mortem examination it was found that the spleen and 

 those glands usually affected in typhoid were somewhat 

 swollen. A. Fraenkel was able to kill monkeys with in- 

 jections of the bacillus, and Chantemesse and Widal point 

 out that they can produce a septicaemia by injecting a con- 

 siderable quantity of a culture of the bacillus into the 

 peritoneal cavity of a mouse. They also found, repeating 

 Fraenkel and Simmonds' experiments of injecting cultiva- 

 tions into the vein of the ear, that, this was followed by 

 diarrhoea and rapid emaciation at the end of several days, 

 although the animals frequently recovered. When they 

 were killed at the height of the disease, lesions corresponding 

 to those met with in typhoid fever were found in the intes- 

 tine, and bacilli were also found in the organs. 



The method that was used in the inoculation of cholera 

 was afterwards resorted to, the contents of the stomach were 

 rendered alkaline, the peristaltic movement of the intestine 

 was paralyzed by means of full doses of opium, and the typhoid 

 bacilli were injected into the alimentary canal ; most of the 

 animals died, and numerous bacilli were found in the intestines 

 and even in the glands, but none could be demonstrated in 

 the blood. It was observed, however, that it was not neces- 

 sary to have an active bacillus present in order to cause very 

 serious symptoms, and even death, with typhoid cultivations ; 

 and it soon came to be recognized that these symptoms were 

 due to regular poisoning or intoxication by toxines and tox- 

 albumens, both of which were described by Brieger as being 

 present in typhoid discharges and in pure cultures of the 



