Sliin Diseases. 273 



origin ; that whicli is dependent on constitutional causeg 

 is more diffused. They depend on the general causes of 

 skin diseases ; — heating, unsuitable diet, sudden changes, 

 imperfect grooming, heats of summer, disorders of the 

 lungs, bowels, liver or kidneys, on oxahc acid in the blood, 

 and some constitutional causes. Beside the scurfinesa 

 and loss of hair, the itching is often so extreme as to ren- 

 der the subject almost unmanageable, and useless for 

 work. 



Treatment. A moderate laxative diet consisting in part 

 of roots (carrots and turnips,) the free administration of 

 alkalies (carbonate of potassa or soda, etc.,) and if still 

 inveterate, a prolonged course of arsenic will be requisite. 

 Locally use mercurial ointment or, if extensive, sulphur or 

 tar ointment, etc. 



BOILS. FURXJNCLES. 



These are too weU known to need description. They 

 consist in circumscribed inflammation of the deep layers 

 of the skin, with pustule and sloughing of a hmited part of 

 the fibrous tissue. They are not uncommon on the legs of 

 horses, and if a number appear in succession are a source 

 of great trouble. 



Treatment. While still a simple inflamed nodule they 

 may often be arrested by incising crucially with a sharp 

 knife and applying cold water bandages. Or apply a 

 poultice or thick wet cloth to bring quickly to a head. If 

 the resulting sore is indolent or unhealthy touch with ni- 

 trate of silver. The free internal use of alkalies (carbonate 

 of soda) sometimes checks their production. 



NEEVOUS lEEITATION OF THE SKIN. NEUBOSIS. PEUEIGO. 



This is often seen in horses that are overfed on grain 

 (especially the more stimulating varieties) and hay, and 

 that have close, unwholesome stables. Hot weather is 

 also a cause. Though occasionally associated with pim- 

 ples or even vesicles, the irritation is found to be equally 



