to exclude scurvy and purpura. Repeated haemorrhages into a joint may
result in appearances which closely simulate those of tuberculous
disease. Recent haemorrhages into the cellular tissue often present
clinical features closely resembling those of acute cellulitis or
osteomyelitis. A careful examination, however, may reveal ecchymoses on
other parts of the body which give a clue to the nature of the
condition, and may prevent the disastrous consequences that may follow
incision.

These patients usually succumb sooner or later to haemorrhage, although
they often survive several severe attacks. After middle life the
tendency to bleed appears to diminish.

_Treatment._--As a rule the ordinary means of arresting haemorrhage are
of little avail. From among the numerous means suggested, the following
may be mentioned: The application to the bleeding point of gauze soaked
in a 1 in 1000 solution of adrenalin; prolonged inhalation of oxygen;
freezing the part with a spray of ethyl-chloride; one or more
subcutaneous injections of gelatin--5 ounces of a 2.5 per cent.
solution of white gelatin in normal salt solution being injected at a
temperature of about 100 F.; the injection of pituitary extract. The
application of a pad of gauze soaked in the blood of a normal person
sometimes arrests the bleeding.

To prevent bleeding in haemophilics, intra-venous or subcutaneous
injections of fresh blood serum, taken from the human subject, the
sheep, the dog, or the horse, have proved useful. If fresh serum is not
available, anti-diphtheritic or anti-tetanic serum or trade
preparations, such as hemoplastin, may be employed. We have removed the
appendix and amputated through the thigh in haemophilic subjects without
excessive loss of blood after a course of fresh sheep's serum given by
the mouth over a period of several weeks.

The chloride and lactate of calcium, and extract of thymus gland have
been employed to increase the coagulability of the blood. The patient
should drink large quantities of milk, which also increases the
coagulability of the blood. Monro has observed remarkable results from
the hypodermic injection of emetin hydrochloride in 1/2-grain doses.

THROMBOSIS AND EMBOLISM

The processes known as thrombosis and embolism are so intimately
associated with the diseases of blood vessels that it is convenient to
define these terms in the first instance.

#Thrombosis.#--The term _thrombus_ is applied to a clot of bloo