From the examination of the blood of tuberculous subjects it appears
that, although the bulk of the coagulum obtained by stirring or
beating is usually greater than that of healthy blood, yet this
coagulum is not composed or well elaborated fibriae, for it is soft
and loose, and contains an unusually large number of colorless blood
corpuscles, while the red corpuscles form an abnormally small
proportion of it. We can understand, therefore, that such a constant
deficiency in capacity for organization must unfavorably affect the
ordinary nutritive processes; and that there will be a liability to
the deposit of imperfectly vitalized matter, instead of the normal
elements of tissue, even without any inflammation. Such appears to be
the history of the formation of tubercles in the lungs and other
organs.

When it occurs as a kind of metamorphosis of the ordinary nutritive
processes and in this manner, it may proceed insidiously for a long
period, so that a large part of the tissue of the lungs shall be
replaced by tubercular deposit without any other sign than an
increasing difficulty of respiration." These views are strongly
corroborated by the following facts:

In making post mortem examinations of persons who have died of
consumption, tubercles of different kinds are found in the same
subject; some of these, having been deposited during what is called
the first stage of the disease before the breathing powers were much
impaired, bear evident traces of organization in the form of cells and
fibers more or less obvious, these being sometimes almost as perfectly
formed as living matter, at least on the superficial part of the
deposit, which is in immediate contact with the living structures
around.