470	PATHOGENIC BACTERIA.
tains gas-bubbles and is sometimes frothy. Occasionally
the patients recover, especially when the infected part is
susceptible of amputation, but death is a more common
outcome. After death the body begins to swell almost
immediately; it may attain twice its normal size and be
unrecognizable. Upon palpation a peculiar crepitation
can be felt in the subcutaneous tissue nearly everywhere,
and the presence of gas in the blood-vessels is easy of
demonstration. The gas is inflammable, and as the bub-
bles ignite explosive sounds are heard.
At the autopsy the gas-bubbles are found in most of
the internal organs, sometimes so numerously as to justify
the German term " Schaumorganen (frothy-organs).
The liver especially is apt to show this frothy con-
dition. When the tissues from such a case are hardened
and examined microscopically it is found that the bub-
bles appear as open spaces in the tissue, the ^borders of
which are lined with large numbers of the gas bacillus.
There are also clumps of bacilli without gas-bubbles, but
surrounded by tissue, whose nuclei show a disposition to
fragment or disappear, and whose cells and fibers show
signs of disintegration and fatty change. In discussing
these changes Ernst1 concluded that they were ante-
mortem and due to the irritation caused by the bacillus.
The gas-production he regarded as postmortem.
In the internal organs the bacillus is usually found in
pure culture, but in the wound it is generally mixed with
other bacteria. On this account it is difficult to estimate
just how much of the damage before death is the result
of the activity of the gas bacillus. That gas-production
after death has nothing to do with pathogenesis during
life is shown by injecting into the ear-vein of a rabbit
a liquid culture of the gas bacillus, allowing about five
minutes' time for the distribution of the bacilli through-
out the circulation, and then killing the rabbit. In a few
hours the rabbit will swell and his organs and tissues
will be riddled with the gas-bubbles.
1 Virchow's Arckiv, Bd. 133, Heft ii.