When leeches are applied to a part, it should be thoroughly freed from
down or hair by shaving, and all liniments, &c., carefully and
effectually cleaned away by washing. If the leech is hungry it will
soon bite, but sometimes great difficulty is experienced in getting
them to fasten. When this is the case, roll the leech into a little
porter, or moisten the surface with a little blood, or milk, or sugar
and water. Leeches may be applied by holding them over the part with a
piece of linen cloth, or by means of an inverted glass, under which
they must be placed.