iderable quantity for some
time previous to death; in others, it is retained, and accumulates to a
great extent in the lungs.

As the disease advances, the action of the heart becomes feeble; and the
appearance of the blood indicates a carbonaceous admixture. The
carbonaceous deposit seems to supersede or supplant the formation of
other morbid bodies in the substance of the lungs--such as tubercle; for
in individuals belonging to families in which there exists an undoubted
phthisical diathesis, tubercle is never found on dissection.

The views expressed in this communication called forth the following
remarks.

PROFESSOR CHRISTISON called attention to the new and important fact, of
the carbonaceous matter being found in the circulating mass. He attached
great importance to Dr Makellar's researches.

PROFESSOR ALLEN THOMSON remarked, that the presence of this carbonaceous
matter in the blood, by no means proved, that it was formed in, or from
the blood.

DR HUGHES BENNETT said, that the antagonism of this carbonaceous disease
to tubercle, was a fact of great interest and importance, especially in
connection with two other recent observations; viz. 1st, That the
depositions of carbon in the lungs of old people, (which French
pathologists describe,) are not found associated with tubercle; and, 2d,
That under the supposed cicatrices of pulmonary tubercular cavities, a
layer of carbonaceous matter is commonly found.

Dr Makellar's paper called forth some interesting observations from the
President, Professor Simpson, and others.

BLACK PHTHISIS,

OR

ULCERATION INDUCED BY CARBONACEOUS ACCUMULATION IN THE LUNGS OF
COAL-MINERS

Among the many diseases incident to the coal-miner, none come oftener
under medical treatment, than affections of the respiratory and
circulating organs. While the collier is subject--during his short but
laborious life--to the other diseases which afflict the labouring
classes in this country, such as inflammations, fevers, acute
rheumatism, and the various eruptive diseases, he, at last, unavoidably,
falls a victim to lesions within the cavity of the chest, arising from
the nature of his employment. In the present communication, it is
proposed to lay before the profession a series of remarks, which I have
been enabled to put together, with a view to elucidate the cause and
progress of that very peculiar pulmonary disease, incident to
coal-miners, which I shall denominate BLACK PH