DISEASES. 603 



much as possible, upon the circumference of the diseased spots, in 

 order to give a supjDleness which would ease the swelling of the 

 uncovered parts. 



Upon the exposure of the disease where it exists, the fici exist- 

 ing on the surface and edges of the velvety tissues are to be 

 removed with the scissors or sharp sage knife ; at the same time 

 the parts of horn which may have remained are to be cut off, 

 avoiding, however, the healthy tissue beneath, which still retains 

 its normal character. 



When the canker is very extensive, so that the wall is loose on 

 each quarter, or on all its circumference, it is of advantage to pro- 

 ceed in the required operations at different times. 



This done, the shoe can be put on ; after which the diseased 

 surface and surrounding horn are to be covered with a thick layer 

 of the medicamentous preparation. If this is in form of a paste, as 

 is often the case, it is sjoread over with a spatula. If in powder, 

 it is thrown over it carefully. If liquid, balls of oakum are soaked 

 with it and placed on, the whole being then kept in place by pads 

 and plates. The important point is that the dressing should be 

 so appHed as to be easily changed, that an exact, regular and 

 sufficiently strong pressure be kept on. No better means can be 

 used for this than the divided plates already referred to. 



In canker the dressing must be renewed every day, and even 

 twice daily at the beginning of the treatment. This is an essential 

 condition of success, whatever may be the therapeutical agent 

 employed ; and this is not a simple difficulty in practice where the 

 patient is not always of easy access. Moreover, this dressing is 

 somewhat complicated, and can only be skillfully made by the vet- 

 erinarian himself. 



It often occurs that upon the removal of the first dressing, (the 

 second day) one finds the tissues already covered by a layer of 

 hardened horn, adherent to the surfaces. One must then, with 

 the finger, a spatula, or a di-y pad of oakum, rub it off where it is 

 found loose and movable and, if necessary, renew the application 

 of the dressing. The same must be done at the other dressings, 

 carefully watching if this new horn thus formed by the influence 

 of the medication, is not separable from the parts underneath by 

 the different morbid secretions of the disease. One must then 

 carefixlly scrape off all that is not adherent, and thin the edges, 

 and the projections of all the horn which retains its soundness; 



