ot required in order to apply
a leech, but also it was soon noticed that leech bites continued to bleed
even after the leech let go, while scarificator incisions often coagulated
before any blood was obtained. In 1884 it was shown by John Berry
Haycroft, a Birmingham chemist, that this phenomenon was due to an
anti-coagulant, now called "hirudin," that the leech injected into the
blood.[181]

To apply a leech, the animal was first dried with a bit of linen, and the
skin of the patient was prepared by washing with warm water and then
shaving. To direct it to the right spot, the leech was often placed in a
small wine glass that was inverted over the area to be bitten. Since
leeches were sometimes perversely unwilling to bite, they were enticed by
the placement of a bit of milk or blood on the patient's skin. Small
children were given one or two leeches, and adults 20 or more. Broussais
employed up to 50 leeches at one time.[182] The leech was usually allowed
to drop off of its own accord when it had satiated itself, which took
about an hour. Sometimes the tail of the leech was cut off so that it
would continue to suck. Once used, leeches could not be reused for several
months unless they were made to disgorge their meal by dropping them in
salt water or weak vinegar. A healthy leech drew one or two fluid drachms
of blood, and as much would flow after the leech had dropped off. Thus a
good Swedish leech could remove about an ounce of blood. This quantity
could be increased by employing a cupping glass over the bite.[183]

Leeches were kept in a glass container of water covered with gauze or
muslin and placed in a cool, dark room. The water had to be changed
frequently, as much as every other day in summer. Pebbles or moss were
placed in the bottom of the vessel to aid the leech in removing the slimy
epidermis that it shed every four or five days. In the nineteenth century
leeches were often sold in drug stores from large, elegant containers with
perforated caps. Actually, only the day's supply of the pharmacist's
leeches was kept in the attractive storefront jars; the rest were kept out
of sight. While most leech jars were simple white crockery pieces with
"leeches" lettered in black on the front, some leech jars were over two
feet tall and decorated with elegant floral and scroll work. Among the
most ornate leech jars were those made in Staffordshire, England.[184]
(Figure 20.)

_Artificial Leeches_

One of the char