inue without sensibly
enlarging; but after a period, hard substances may with the fingers be
detected beneath it. These hard bodies are faeces, which accumulate within
the rectum, and often in so great a quantity as to seriously inconvenience
the animal, rendering it dull and indisposed to feed.

Before attempting to direct the treatment for these cases, it is necessary
the nature of the affection should be fully explained. The enlargement, to
which attention is at first solely directed, is always of secondary
consideration. The dropsy is merely a symptom indicative of the loss of
tone of the adjacent parts, of which the rectum is by far the most
important. If this circumstance be not observed, but the swelling be
treated as if it was all the practitioner had to contend with, he will in
the end learn his mistake. The intestine loses its tonicity; it no longer
has power to contract upon or to expel its contents; it becomes paralysed,
and the dung consequently accumulates within it, distending it, and adding
to its weakness by constant tension. The rectum at length retains no
ability to perform its function; but the sphincter of the anus, or the
circular muscle that closes the opening, appears to gain the strength of
which the intestine is deprived. It contracts, and thus shuts up the
faeces which the rectum cannot make an effort to dislodge; and in this
circumstance the physiologist sees evidence of the sources whence the
different parts derive their contractility. The rectum, like the other
intestines, gains its vital power from the sympathetic nerve, or that
nerve of nutrition and secretion which presides over organic life. The
muscle of the anus, on the other hand, is influenced by nerves derived
from the spinal column; and thus, understanding the two parts obtain their
motor power from different sources, the reader will comprehend how one can
be incapable of motion while the other is unaffected, or rather excited;
for the presence of the retained dung acts as an irritant, and provokes
the anus to contract with more than usual vigor.

If nothing be done to restore the balance of power, the rectum speedily is
so much distended that its walls become attenuated, and then a cure is
hopeless; a sac is formed, and the gut is not only much stretched or
enlarged, but it is also, by the excessive bulk of its contents, forced
from its natural position, being carried either to one side or the other,
but always to where the drops