OPERATIONS. 437 
that the absence of them may entail the least possible inconvenience upon 
the animal. Thus, if the carotid artery be lost, place the food low down, 
and thereby aid the flow of blood to the head. If the jugular vein be 
destroyed, then put the fodder high up, that the curreat from the head 
may be facilitated. 
Never, on any account, remove any portion of skin which is not 
involved in some fearful injury, or separated from its attachments by the 
action of disease. , 
Skin is the part of the body which is never reproduced, and even the 
place whence it is absent always heals slowly. However loose the skin 
may appear, however disproportioned it may seem after some tumor has 
been removed, respect every particle of it. Before the wound can heal, 
inflammation must set in. That process ended, the skin, under its action, 
will have contracted, and in the end there will be only sufficient integu- 
ment to cover the part; whereas, if the slightest amount be excised, to 
such an extent there will for a long time remain a gaping sore. 
Never spare the knife. Think well before you touch that tool; but, 
having it in hand, assure yourself its edge is sharp, and never do at two 
euts that which might have been accomplished in one. 
Always slit up a sinus where such a proceeding is possible. When 
the sinus is too long, supposing the pipe to take an internal direction, 
as from the withers to the chest, insert a seton with the guarded seton 
needle, a representation of which is given below. 
THE GUARDED SETON NEEDLE. 
The blade of this instrument is generally about two feet long. Before 
using it, the cutting head is always retracted by pulling back the nut at 
the extremity, and securing it in its place by means of the screw situated 
on the middle of the handle. The blade then reposes upon a blunt 
companion, and may with impunity be inserted down any sinus or false 
canal. Having reached the bottom of the pipe, and all important vessels 
being passed, the screw is loosened, and the projecting end of the blade 
at the extremity of thé handle is struck forcibly, when the sharp point 
is driven forward, and this pierces the flesh. 
THE SETON NEEDLE PROTRUDED, AND SECURED WITHIN THE HANDLE BY MEANS OF A SCREW. 
Behind the cutting head there is a free space. Through that opening 
along piece of tape is threaded, and the instrument is withdrawn, pull- 
