234 THE MICROSCOPE. 
CONCERNING THE DIFFERENTIATION OF BLACK PIG- 
MENT IN THE LIVER, SPLEEN AND KIDNEYS, 
FROM COAL-DUST DEPOSITS.* 
FREDERICK GAERTNER, 
A. M., M. D., UNIVERSITY OF STRASSBURG, GERMANY; M.D., ST. LOUIS MED, COLLEGE; A, B., MOUND 
CITY COLLEGE, ST. LOUIS; CERTIFICATE ILLINOIS STATE BOARD OF HEALTH; CERTIFI- 
CATE OF ENDORSEMENT FROM UNIVERSITY OF PENNSYLVANIA; MEMBER IRON CITY 
MICROSCOPICAL SOCIETY. AND OF THE AMERICAN SOCIETY OF MICROSCOP- 
ISTS; MEMBER GERMAN SOCIETY PHYSICIANS AND SURGEONS OF 
BERLIN; HON. MEMBER OF PHYSICIANS AND SURGEONS 
OF VIENNA; CORRESPONDING PHYSICIAN TO THE 
STRASSBURG PATHOLOGICAL SOCIETY, 
ETC., ETC. 
[PLATES IX, X AND XI. | 
OTH resist the various reagents, acids and alkalies; both lie for 
the most part within the smaller arteries. The difference 
exists on the one hand, in that the anthracotic pigment lies princi- 
pally within the cells (Leucocytes), which is very unusual for 
micrococci; on the other hand—and this is the principal difference— 
in its relation to the different coloring fluids, especially anilin 
colors, and also to reflected and direct light. To distinguish the an- 
thracotic pigment from fatty degenerated epithelial cells, fatty 
particles, etc., it is sufficient to note that the anthracotic pigment 
is not affected by the means that are used for recognizing fatty 
degenerations—such as osmic acid, sulphurie ether, ete. Finally, 
concentrated mineral acids serve to distinguish the anthracotic 
pigment from the putrid products of the epithelial cells, which, 
especially in the treatment with acetic acid, under the microscope, 
appear to be entirely black. But with mineral acids the epithelium 
cells immediately dissolve, while the pigment, as before stated, 
remains unchanged. 
It appears from my (pathological) investigations, as the follow- 
ing protocols more minutely describe, that in these cases the intensity 
of the black pigmentation in the abdominal organs increases in exact 
proportion to the quantity of coal dust in the bronchial lymphatic 
glands, so that it increased according as the walls of the neighboring 
blood vessels of the slaty bronchial lymphatic glands were penetrated 
by the anthracotic substance. 
Since the cases of my investigation in this respect are of some 
importance and support the theory that the black pigmentation of the 
abdominal organs is anthracotic, and not that of melanotic, I there- 
fore annex the results of my investigations of ten cases: 
* Continued from page 204. 
