432 THE BACILLUS OF TYPHOID FEVER. 
the bacillus under consideration bears a causal relation to typhoid 
fever. Eberth was only successful in finding the bacillus in the 
lymphatic glands or in the spleen in eighteen cases out of forty in 
which he searched for it. On the other hand, he failed to find it in 
eleven cases of various nature—partly infectious processes—and in 
thirteen cases of tuberculosis in which the lymphatic glands were 
involved, and in several of which there was ulceration of the mucous 
membrane of the intestine. 
‘Koch, independently of Eberth and before the publication of his 
first paper, had found the same bacillus in about half of the cases 
examined by him, and had pointed out the fact that they were lo- 
cated in the deeper parts of the intestinal mucous membrane, beyond 
the limits of necrotic changes, and also in the spleen, whereas the 
long, slender bacillus of Klebs was found only in the necrosed por- 
tions of the intestinal mucous membrane. 
The researches of W. Meyer (1881) gave a larger proportion of 
successful results. This author confined his attention chiefly to the 
swollen plaques of Peyer and follicles of the intestine which had not 
yet undergone ulceration. The short bacillus which had been de- 
scribed by Eberth and Koch was found in sixteen out of twenty cases 
examined. The observations of this author are in accord with those 
of Eberth as to the presence of the bacillus in greater abundance in 
cases of typhoid which had proved fatal at an early date. 
The fact that in these earlier researches the bacilli were not found 
in a considerable proportion of the cases examined is by no means 
fatal to the view that they bear an etiological relation to the disease. 
As Gaffky says in his paper referred to : ; 
“This circumstance admits of two explanations. Either in those 
cases in which the bacillus has been sought with negative results 
they may have perished collectively, before the disease process which 
thev had induced had run its course ; or the proof of the presence of 
bacilli was wanting only on account of the technical difficulties which 
attend the finding of isolated colonies.” 
Gaffky’s own researches indicate that the latter explanation is the 
correct one. 
In twenty-eight cases examined by this author characteristic 
colonies of the bacillus were found in all but two. In one of these, 
one hundred and forty-six sections from the spleen, liver, and kid- 
neys were examined without finding a single colony, and in the other 
a like result attended the examination of sixty-two sections from the 
spleen and twenty-one sections from the liver. In the first of these 
cases, however, numerous colonies were found in recent ulcers of the 
intestinal mucous membrane, deeply located in that portion of the 
tissue which was still intact. These recent ulcers were in the neigh- 
