ty of infection of a wound
with cancer when operating for the disease. A cancer should not be cut
into unless this is essential for purposes of diagnosis, and the wound
made for exploration should be tightly closed by stitches before the
curative operation is proceeded with; the instruments used for the
exploration must not be used again until they have been boiled. The
greatest care should be taken that a cancer which has softened or broken
down is not opened into during the operation.

Investigations regarding the cause of cancer have been prosecuted with
great energy during recent years, but as yet without positive result. It
is recognised that there are a number of conditions which favour the
development of cancer, such as prolonged irritation, and a considerable
number of cases have been recorded in which cancer of the skin of the
hands has followed prolonged and repeated exposure to the Rontgen rays.

_The Alleged Increase of Cancer._--Regarding the alleged increase of
cancer, it may be pointed out that it is impossible to ascertain how
much of the apparent increase is due to more accurate diagnosis and
improved registration. It is probable also that some increase has taken
place in consequence of the increased average duration of life; a larger
proportion of persons now reach the age at which cancer is frequent.

_The prognosis_ largely depends on the variety of cancer and on its
situation. Certain varieties--such as the atrophic cancer of the breast
which occurs in old people, and some forms of cancer in the rectum--are
so indolent in their progress that they can scarcely be said to shorten
life; while others--such as the softer varieties of mammary cancer
occurring in young women--are among the most malignant of tumours. The
mode in which cancer causes death depends to a large extent upon its
situation. In the gullet, for example, it usually causes death by
starvation; in the larynx or thyreoid, by suffocation; in the intestine,
by obstruction of the bowels; in the uterus, prostate, and bladder, by
haemorrhage or by implication of the ureters and kidneys. Independently
of their situation, however, cancers frequently cause death by giving
rise to a progressive impairment of health known as the _cancerous
cachexia_, a condition which is due to the continued absorption of
poisonous products from the tumour. The patient loses appetite, becomes
emaciated, pale, and feverish, and gradually loses strength until he
d