THE MIOEOBES OF HUMAN DISEASES. 193 



always hypertrophied and softened in typhoid patients. 

 The round red spots which may be observed upon the 

 skin are distinctive marks of the affection of the diges- 

 tive canal, and it has occurred to Bouchardat that if, as 

 he supposes, these spots contain the same microbe as that 

 of the intestines, it might be cultivated and attenuated 

 into a true vaccjne. 



The presence of special microbes in typhoid fever 

 was first observed by Kecklinghausen in 1871, but the 

 exact description of the typhoid bacillus has been only 

 recently given by Eberth and Klebs. 



Eberth has observed this bacillus in the spleen, 

 the lymphatic glands, and the intestines, making 

 use of special staining processes. It appears in the 

 form of short rods with rounded extremities, in the 

 tubular glands and round the bottom of these glands, 

 which cover the mucous membrane of the intestine. 

 They are numerous when the ulceration of Peyer's 

 glands begins; afterwards they become fewer, and 

 are succeeded by other microbes. From the position 

 of the bacteria in a section of the mucous membrane, 

 it may be seen that they penetrate through its surface, 

 and fasten on the ulcerated and mortified tissue 

 (Oornil). 



Blood taken from living patients often displays 

 bacilli amid the red corpuscles (Fig. 86). The spleen, 

 which is always hypertrophied, contains the same 

 bacillus, which is also found in the liver, and some- 

 times in the kidneys and urine. 



