DISEASES. 607 



followed by a few who prefer it to the simple operations of Solley- 

 sel, which consists in the division of the loose pieces of horn and 

 the excision of the fungoid projections. 



We have thus far only spoken of the local, without referring to 

 the internal or constitutional treatment of canker, recommended 

 by those who look upon the disease as constitutional. Without 

 beUeving that it can have any real curative effect, we, however, 

 admit its usefulness, when the disease is of old standing, and that 

 the animal has suffered much by it. Ferruginous preparations 

 are specially advisable, and we prefer the carbonates that are used 

 by Delwart to the sulphates recommended by Prevost, Delaval 

 and Hertwig, and it is well to unite them with bitters and tonic 

 powders. Arsenious acid is prescribed internally by Delaval, 

 FeuiUette, Niederberger, Obich ; and other alteratives, such as 

 mercury, which we would not advise. Nor can we understand 

 how any benefit is to be derived from diuretics and purgatives, 

 and especially from the use of external emunctories, such as 

 setons. 



Corns. 



Under this name is understood an alteration of the tissues 

 underneath the hoof ; of the heels of the horse's foot by lesions of 

 the living parts in the movements of expansion of the hoof ; by 

 bruises, compressions or contusions. There is then a capillary 

 hemorrhage which extends in ecchymosis in the hoof. A com, 

 then, is a bruise of the Hving horn at the extreme end of the 

 branches of the sole, and especially in the laminated tissue of the 

 folds of the bars. It is a very common disease, and one to which 

 all horses are exposed. Some have them constantly. 



Corns are seen mostly on the fore feet, and on the inside 

 more commonly than on the external side. They are rare on the 

 hind feet, because in the various gaits the weight of the body is 

 carried more on the front legs and on the posterior part of the 

 foot, while in the hind legs it is the front part which principally 

 receives it. 



I. Divisions.— LaioBse Sr., has distinguished them into natural 

 and accidental, whUe Girard considers them all as accidental. H. 

 Bouley designates as essential those which come from other than 

 external causes. We believe that it would be better to estabUsh 

 the divisions on pathological and anatomical bases, and admit a 



