AETIOLOGY OF TUBERCULOSIS. 
211 
rection again and by the lymph-stream be carried into the blood. I do not 
doubt that, as in almost every case of miliary tuberculosis, the point of depar¬ 
ture for the infection can be shown, one can also succeed in all cases of local¬ 
ized tuberculosis of the inner organs, as well as of the bones and joints, when 
they are dissected to find some older tuberculous herd, mostly perhaps caseous 
bronchial glands, from which single bacilli could get into the blood. It is very 
probable also, that tuberculous bacillar meningitis of children in so far belongs 
here, as that in the same, although lungs, liver and spleen are very often free 
from tuberculosis, the bronchial glands are almost regularly found caseous, 
whence we may conclude that these latter in this case too are to be considered 
as the primary disease-herd. To be sure it is peculiar, that in this form of 
tuberculosis, in which plainly not single but numerous tuberculous bacilli are 
deposited by the blood, the pia mater is so favored a place of deposit. 
If, as has already been shown in former parts of this work, the various 
forms of tuberculosis must be declared identical on account of the same quali¬ 
ties of the bacilli occurring in them and the cultures gained from these, as well 
as on account of the identity of the inoculating products proceeding from them, 
the progressive knowledge of their mode of originating gives new proofs of 
this supposition. At first sight, however different the forms of lung-phthisis, 
acute and chronic miliary tnberculosis, the affections of the glands and mucous 
membrane under the general figure of scrofula, tuberculosis of the bones and 
joints, of localized tuberculosis of single organs, as for example the kidneys 
and the intestines, may appear, we shall see without difficulty that they belong 
together when we look at their mode of formation. Only lupus offers in so far 
a certain difficulty in the identification with tuberculosis, as clinic observation 
state a distinction that cannot be overlooked in the conduct of lupus and un¬ 
deniably tuberculous affections of the skin and mucous membrane. Neverthe¬ 
less the ^etiological reasons for the unity of these two diseases are too weighty 
to retire before this difference, which possibly may find its explanation in the 
individual disposition. 
The relation is similar between the tuberculosis of animals, above all of 
perlsucht and tuberculosis in man. These also must on account of the identity 
of the parasites on which they are conditioned, be held to be identical with 
human tuberculosis in spite of the differences in the anatomical behavior and 
in their clinical course. It has, to be sure, been stated, especially with refer¬ 
ence to perlsucht, that the transmission of this disease to man has not yet been 
certainly proved. On the other hand the following may be said : On account 
of the very slow development of the disease, the place and time of the infec¬ 
tion and therewith the source of the same can no longer be confidently stated, 
when the first plain symptoms appear. On this account in the frequent inha¬ 
lation-tuberculosis the mode of infection can be determined in a scientific 
manner only in comparatively few cases. Still less will this be possible in the 
much rarer cases of intestinal tuberculosis arising from the use of flesh or milk 
of cattle suffering from perlsucht, because here the uncertainty is heightened 
by the easily possible confusion with other much more frequent kinds of in¬ 
fection. It is therefore very questionable whether ever a case of human tuber¬ 
culosis can without criticism be attributed to the use of the meat or milk of 
