Seatons and Blisters 139 
are applied with aseaton. Seatons are used when a mild, 
but long-continued counter-irritant is wanted. 
Blisters.— The two substances commonly used for 
blisters are pulverized Spanish flies (Cantharides) and 
the biniodid of mereury. The former makes what is 
commonly known as a “fly-blister.” The latter, from 
its color, is commonly called a “red-blister.” These 
blisters are made by thoroughly mixing one part by 
weight of the drug and eight parts of fresh lard or 
vaseline. Both of these blisters are poisonous, and 
should be cared for accordingly. If it is desired to 
remove bunches, especially bony bunches, the red-blister 
is commonly preferred ; for ordinary purposes, the fly- 
blister is used. Neither kind should be applied to a 
raw surface or over a very large area, for it may be 
absorbed and prove injurious to the animal. 
The hair should first be clipped from the area, 
after which the blister is rubbed in with the fingers 
from three to ten minutes, depending on how severe 
an irritation is desired. In most cases, a light blister 
repeated is more effective and more satisfactory than 
a single severe one. Horses with thick skin re- 
quire the blister to be rubbed in longer than thin- 
skinned, nervous ones. The blister should be left on 
from twenty-four to thirty-six hours, or until a watery, 
gummy fluid exudes from the skin and sticks the hair 
together. Then the area should be thoroughly washed 
with warm water and soap, wiped dry and greased 
with fresh lard or vaseline. 
If the blister is applied to the hind legs, or to any 
place which the horse can switch, the tail should be se- 
