252 BACILLI PATHOGENIC IN MAN. 



known that a group of fairly widespread organisms, 

 which, however, differ totally from the typhoid bacilli, 

 have this property in common, that when introduced 

 either hy intravenous or subcutaneous injection, they 

 kill animals with the symptoms of a gastro-enteritis, 

 often with marked swelling and ulceration of Peyer's 

 patches. It is probably to these organisms that we 

 must ascribe the apparent positive results which certain 

 authors think they have obtained by inoculation of the 

 typhoid bacilli ; this remark applies more especially to 

 the typhoid cultivations isolated by Tayon, and tested 

 with apparent success on animals and man, for these in 

 no respect correspond to the characters of pure cultiva- 

 tions of the characteristic bacilli which constantly occur 

 in typhoid fever. Recently numerous experiments have 

 been made by Gaffky (and also in the laboratory at 

 Gottingen) with the view of setting up a corresponding 

 disease in animals with pure cultivations of the typhoid 

 bacilli. Besides rabbits, guinea-pigs, and rats, calves 

 and monkeys have also been employed in these experi- 

 ments ; infection has been attempted by continued feed- 

 ing, in some cases along with simultaneous employment 

 qf various medicinal substances, by subcutaneous and 

 intravenous injections, and by inhalations, but as yet 

 without any positive result. However, there is always 

 the possibility that some preliminary preparation of the 

 animals may render them susceptible to an infection. 

 The success of such experiments would be of great 

 importance in completing the proof that the bacilli 

 described are really the causal exciting agents of typhoid 

 fever, although the constancy of their occurrence and 

 their exclusive presence in this disease leaves scarcely 

 any real doubt as to their significance. 

 Occurrence of Typhoid bacilli have never as yet been demonstrated 

 with certainty outside the human body with the excep- 

 . tion of pf e iff er s demonstration of their presence in 

 the dejecta of typhoid patients. It is true that there 

 are statements by Brautlecht and Klebs as to the suc- 

 cessful demonstration of typhoid bacilli in suspected 

 drinking water ; but according to the description which 



