BACILLUS TYPHI ABDOMINALIS. 253 



these authors give of the bacilli found by them it is 

 certain that neither of them were dealing with typhoid 

 bacilli. Brautlecht's bacilli were very thin, slender 

 bacilli ; those isolated by Klebs from the water supply of 

 Ziirich were not decolourised by Gram's method, they 

 showed another mode of spore formation, were infective 

 for rabbits, and were therefore certainly not identical 

 with the bacilli of Eberth and Gaffky.* 



The most distinctive character of the typhoid bacilli 

 is their peculiar mode of growth on potatoes ; and when 

 we have to diagnose these organisms the potato cultiva- 

 tions must be employed as the distinctive criterion. 

 With the help of this aid to diagnosis it will now per- Modes of 

 haps be possible to follow more closely the distribution 

 of the typhoid bacilli in our surroundings and the modes bacilli - 

 in which it causes infection. What has as yet been 

 done in this direction rests only on deductions and on 

 practical experience and statistical facts which are in 

 many respects open to question, and are in part contra- 

 dictory. The following views may be deduced from the 

 knowledge which we have gained during recent years as 

 to the specific exciting agents of typhoid fever. 



We may perhaps conjecture that the seat of entrance 

 of the infective agents is by preference the digestive 

 tract ; in favour of this we have the observations as to 

 the distribution of the typhoid bacilli in the body of the 

 patient as well as the analogy with many other diseases 

 which are chiefly localised in the intestine (swine ery- 

 sipelas, cholera). Nevertheless, in spite of these obser- 

 vations and analogies, the possibility of some other seat 

 of invasion is not excluded (see the chapter on the causa- 

 tion of disease). Further, from the mode of spread of 

 typhoid epidemics we may probably draw the conclusion 

 that a certain preparation of the intestine for infection 



* Kleb's article, "Bacillen," in Eulenburg's Realencyclopcedia. 

 Lfc'ure on the drinking water supply of (he town of Zurich and its suburbs. 

 Auasersihl, 1885. Compare the refutation by Cramer in Die Wasser- 

 venorguny von Zurich, Zurich, 1885 ; and Die Wasserversorgung von 

 Zurich und Ausgemeinder ; Entgegnung der erweiterten Wasser-com- 

 mission auf die Angriffe von He,rrn Prof. Klebs. Zurich, 1885. 



