CHAP. II.] OPERATIONS ON, AND DISEASES. 159 



than those of the male ; a circumstance to be re- 

 membered when we come to treat of the disorders 

 incident thereto, since in inflammation of its neck, 

 for example, in one sex we are obliged to have re- 

 course to instruments, in the other, the urine may 

 be discharged by the fingers. But it so happens 

 that horses are more liable to the disorders just 

 named than mares, by reason of that very circum- 

 stance — namely, the length of the neck. The 

 reader will also please to notice, that the thin mem- 

 brane (termed peritonceum, see page 140), which 

 defends the whole intestine against the friction of 

 the surface, reaches backward to only about half 

 way over the bladder ; so that it offers no ob- 

 struction to our operations upon its neck in cases of 

 disease, but rather contributes to the expulsion of 

 the urine ; as it does also to promote disease of these 

 organs, whenever the said peritonceum being in- 

 flamed and thickened [" inflammation of the in- 

 testines"] it then presses hard upon the fundus or 

 bottom of the bladder, which, in the living animal, 

 lies forward, and thus compels the neck to collapse, 

 to get into folds, or to become inflamed. See 

 " Urinary organs — diseases of," in Inclex. 



57. To recur once more to the subject of a pre- 

 ceding section (the 55th) — the principle (of urea) 

 that resides in any given quantity of urine evacuated 

 by the horse, it may be here observed, that when 

 the animal, on a journey, has been pushed onward, 

 and thus prevented from staling for a considerable 

 time, he at length produces it of a deeper colour 



