178 ORIENTAL PLAGUE chap. 



parts of the intestinal wall ; and further, in the mesenteric 

 glands, whence the vascular system of the other viscera 

 become crowded with the bacilli. 



(4) That the positive results obtained by feeding with 

 semi-dried or more completely dried gelatinous plague 

 materials — e.g. gelatine cultures and plague organs dried 

 by themselves or mixed with food -stuffs (wheat, rice, flour) 

 — are in marked contrast to the negative results of feeding 

 with fresh plague materials — e.g. fresh milk cultures, broth 

 cultures, watery emulsions of cultures of B. pestis and 

 fresh plague organs. 



(5) That it is, therefore, justifiable to assume that the 

 positive results in the former cases are due to the gastric 

 juice failing to reach the central portions of the infective 

 food particles, the plague bacilli in these central portions 

 being left undisturbed and unaffected owing to the pro- 

 tection afforded them by the outer dried shell of material. 



In a word, I am inferring that on their passage through 

 the stomach the infective materials would retain some of 

 the plague bacilli protected and living ; that on reaching 

 the ileum the infective particles would, by the absorptive 

 tendency of the Peyer's glands, become fixed, as it were, 

 on these glands, and that the living plague bacilli within 

 the material thus affixed to the mucous membrane would 

 at once commence to multiply in situ, causing thereby 

 the changes which were actually found, viz. haemorrhage 

 and necrosis and charging of the absorbents with B. pestis, 

 with the result of general infection of the rest of the body. 1 



1 As direct evidence bearing on this point, the following observation deserves 

 to be mentioned : — 



A guinea-pig was inoculated cutaneously, on April 11, with a particle of the 

 spleen of a rat dead of acute plague. This guinea-pig was found dead on April 17, 

 showing the following post-mortem appearances : large necrotic bubo with 

 haemorrhage around it, while the spleen, liver, and lung contained numerous 



