ence of the carbonaceous
disease, instead of the true phthisis; for, in all the _post-mortem_
examinations which I have conducted, connected with this pulmonary
affection, I have never found tubercular deposit:--while other members
of the same family, having a like predisposition, and who never entered
a coal-pit, have died of phthisis. Can carbon inhaled destroy a
tubercular formation? I never knew or heard of a case of black spit in
a female collier, and this is accounted for by the circumstance, that
the women, when permitted to labour, previous to the late prohibitory
enactment, were only occupied as carriers; and from their movements
towards the pit shaft, in transporting the coals, were enabled to inhale
at intervals a purer atmosphere. The boys also, who were employed as
carriers to the pit shaft, continued to labour with like impunity, from
their occasional change of situation; but the miner, lying on his side
in a confined, smoky recess, under ground, gasping for breath,
proceeding with his exhausting labour, cannot fail, in his deep
inspirations, to draw in the deleterious vapour, to the most minute
ramifications of the pulmonary structure, and, as he daily repeats his
employment, so does he daily add to the accumulation of that foreign
matter which shall ultimately disorganize the respiratory apparatus. In
the first stage of the affection, there is an incessant dry cough,
particularly at night, and all the prominent symptoms of bronchitis are
present. Indeed, from the time a man becomes a coal-digger, and inhales
this noxious air,[6] there is ever after a manifest irritation in the
lining membrane of the respiratory passages, which is apparent before
carbon in any quantity can be supposed to be lodged in the lungs. The
mucous membrane of the air passages, by its continually pouring out a
viscid fluid, has the power of removing any foreign matter that may be
lodged in them. Now, should this membrane, owing to previous irritation,
lose to a certain degree this secretory power, then the foreign body
adheres to it, and is retained, and this, I think, constitutes the
preparatory stage of black deposit. In tracing the progress of the
disease, it is my belief, that immediately after the carbon is
established in the air-cells, the absorbents become actively engaged,
and the glandular structure soon partakes of the foreign substance. One
of the peculiar features, as we shall find, when we come to describe
cases, is, th