188 OPERATIONS ON THE SKIN AND CELLULAR TISSUE. 



special periods or seasons of the year, and have thus invented the 

 seton of prevention or of precauiion, but without satisfactorily 

 demonstrating what is to be prevented, or what anticipated. The 

 theory, if any, in which such an assumption originates cannot be 

 certified, and honest veteriaarians cannot themselves identify it 

 with such a practice or pretext. 



If exutories are a frequent resort, and are highly appreciated 

 in veterinary surgery, and their general use is commonly unat- 

 tended with danger, yet they are not always so absolutely harm- 

 less that they may be trifled with, and prescribed without due 

 consideration of the peculiar conditions under which their use is 

 contra-indicated. It cannot be rationally supposed that the 

 potency to which they owe their beneficial effect when rightly 

 du-ected is to vanish when it is erroneously applied, and that it 

 can be made innocuous by misdirecting it. Animals debilitated by 

 hea\'y work or by disease ; those affected with chronic organic 

 ailments; those threatened with eruptive diseases, or suffering 

 with septic complaints; none of these are fit subjects for the 

 application of exutories. 



SETONS. 



A seton is a form of exutory which consists in the introduction 

 of a foreign substance under the skin, ordinarily a band of linen 

 tape, or a leather ring. The former is known as the tape seton, 

 while the second is more appropriately termed a rowel. 



Tape Seton. 



This is usually merely a piece of clean, white tape, of suitable 

 width and length as required by the case. In some circumstances, 

 however, cords or braids of lint or horse-hair are substituted. 

 The seton may either be introduced under the skin alone and 

 dry, or it may be saturated with some irritating fluid, or covered 

 with a stimulating ointment, to increase its effect and promote the 

 purulent secretion. The operator must not fail to allow a suffi- 

 cient length to securely tie the ends which pass out at the two 

 openings of the tract through which it is drawn. Yet they are 

 not always secured by an ordinary knot, but are quite generally 

 united by a species of twist upon their extremities, which can be 

 readily loosened when it becomes necessary. This knot must be 

 sufficiently wide and strong to prevent it from sHpping thi-ough 



