GEEASE. 167 



ganic membrane, serving as an envelope to the true 

 skin. It is everywhere pierced with holes, correspond^ 

 ing in size, situation, and number, to those of the cutis 

 (or real) skin. 



' First, there are the pores for the hairs; secondly, the 

 perspiratory or exhalent pores ; thirdly, the absorbent 

 or inhalent pores ; and fourthly, pores of a larger size, 

 through which unctuous secretions in various parts are 

 emitted.' 



It will be seen from the above extracts that, unless 

 the external skin be kept thoroughly clean by good 

 grooming, the pores must become clogged and unable 

 to perform their functions, which consist in carrying 

 off the corruption of the system through the perspira- 

 tory pores, thus relieving the blood of a large quantity 

 of water, saline, and animal matters, which, if confined, 

 are dreadfully injurious to the system. 



I will now proceed to consider 



GEEASE. 



Grease consists of a morbid secretion of the glands 

 or pores of the extremities. 



In slight cases the skin becomes inflamed, swelled, 

 and subsequently cracks, and presents numerous small 

 fissures in the heels of the fore or hind legs, but in 

 more severe cases ulceration, and then fungous tumours 

 or ( grapes,' take place. 



Debility is the chief cause of this disease, which is 

 proved by its frequent occurrence among coarse, half- 



