Leeches were gathered in the spring of the year either by means of a pole net, or, more primitively, by wading into the water and allowing the leeches to fasten themselves onto the legs. Sometimes horses and cattle were driven into the water to serve as bait for the leeches.[175] (Figure [19].)

[Larger Image]

Figure 19.—Lithograph published in London in 1814 showing three women gathering leeches by a stream. (NMHT 320033.08; SI photo 76-7741.)

Leeching, like other forms of bloodletting, enjoyed a revival in the early nineteenth century, particularly in France, where the doctrines of heroic medicine preached by Broussais[176] led to an increase of leech usage from about 3 million in 1824 to 41.5 million in 1833.[177] Leechers, although not as high in status as professional cuppers, practiced in many large cities, and numerous tracts were written on the care and breeding of leeches. “Leech farms” were unable to increase the leech supply to meet the rising demand, and most leechers complained of the scarcity and great expense of the little animals.[178]

Leeching and cupping each had their advocates. The major advantage of the leech over the cup was that the leech could be employed on almost any part of the anatomy, including around the eyes, in the mouth, the anus, and the vagina. In fact, leeching the internal membranes enjoyed quite a vogue in the early nineteenth century. Leeches were applied to the larynx and the trachea for bronchitis and laryngitis and for relieving the cough of phthisis. For inflammations of the conjunctiva (the membrane lining the eyelids) they were applied to the nasal membrances of the adjacent nostril, and for inflammations of the ear they were applied to the meatus of the ear and behind the ear. The French popularized the practice of leeching the anus to treat inflammations of the mucous membranes of the bowel. To prevent leeches from getting lost in the body cavities, Jonathan Osborne, a British physician, recommended in 1833 that a thread should be passed through the leech’s tail. In addition, he invented a device, which he called a “polytome,” specifically for introducing leeches into the rectum.[179] In the mid-nineteenth century, special leech tubes were widely sold for applying leeches to internal membranes.[180]

A second advantage of leeches over cupping was that leeches could extract blood more readily. Not only was dexterity not 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].)