of poultices or anointing the tissue with oils and fats will be
found beneficial in hastening the dead tissue to slough off. When the
outer skin begins to suppurate, it should be removed with a pair of
pincers, and the patch treated as an open wound. In moist gangrene the
tissue should be thoroughly disinfected with a 3 per cent solution of
compound cresol, or particularly an alcoholic tincture of camphor.
Continuous irritation with antiseptic fluids prevents the accumulation
and absorption of poisonous liquids. Incisions into the dead tissue may
be made, and when sloughing commences the tissue should be removed with
forceps and the resulting wound treated as in dry gangrene.

ULCERATION.

An ulcer is a circumscribed area of necrosis occurring on the skin or
mucous membrane and covered with granulation tissue. It is a process of
destruction, and when this process is going on faster than regeneration
can take place, we have a gnawing, or eating, ulcer. When such an ulcer
increases rapidly in size it is termed a phagedenic ulcer. A fungoid
ulcer is one in which the bottom of the ulcer projects beyond the edge
of the skin. These ulcers secrete milky or bloody-white liquid called
ichor. When the ulcer is of an ashen or leaden color, with the bottom
and sides formed of dense, hard connective tissue, which gives but
little discharge and is not sensitive, it is termed callous, torpid, or
indolent ulcer.

_Causes._--As in the case of gangrene, disturbances of circulation are
among the most frequent causes. A wound to a tissue with slight
recuperative power may be followed by ulceration, as in tumors. Certain
germs may produce ulcers, as the glanders bacilli, which cause the
ulcerations on the nasal septum in glanders.

_Treatment._--This consists in removing the exciting cause at once. The
secretions of the ulcer should be washed off with antiseptic solutions
and the formation of granulation tissues stimulated by antiseptic
salves, such as carbolated vaseline, lead ointment, or by dressings of
camphor. Air should be kept from the ulcer by occlusive dressings. Where
the ulcers are inflamed, warm lead water or lead water and laudanum will
be found efficacious. Callous ulcers are best removed by a curette,
knife, or hot iron and then treated like a common wound. Mechanical
irritation should be avoided.

ABSCESSES.

These consist of accumulations of pus within circumscribed walls, at
different parts of the body, and may