This, whenever it occurs, provokes great vexation. Generally it affects animals of the highest value or of fast capabilities, which are used only for saddle purposes. The affection consists of a patch of horn, resembling a corn upon the human foot. These patches are not absolutely large, though of course in size they vary. Neither are they all similar in form or in thickness. In one respect, however, a family likeness runs throughout the kind. They are not simple corns, but their different nature is shown by a margin of ulceration. The situation which they invariably occupy is under the saddle-tree. Their presence, of course, obliges the horse to be disused; and they are the more annoying, since there is no chance of these comparatively trifling ailments disappearing without treatment. The treatment, moreover, cannot be speedy. Whatever measures may be resorted to, time is necessary for the cure; and, during this space, the proprietor sees his horse in high health and spirits, but is forbidden to mount it because of a petty blemish which, in his eyes, is perfectly contemptible. [Illustration: A SITFAST, AS IT APPEARS UPON A HORSE'S BACK.] Sitfasts, though all said to be caused by the friction of the saddle, have several distinct excitants. The saddle is without life, and cannot of itself injure the quadruped. It is common to account for a sitfast by saying the saddle does not fit. Such may occasionally be the case; for a saddle, if badly made, will chafe the skin and produce a sitfast. But this cause is in operation less often than is imagined. A retired surgeon, whom the author had the honor of visiting at Reigate, wore a cork leg. That gentleman stated that, whenever the leg used to chafe the stump to which it was attached, he always considered his body was out of order. Medicine then was taken, and the symptom disappeared. We mortals refuse to think the horse ails anything unless the animal is alarmingly prostrated. All smaller ills are disregarded; yet that derangement of the stomach which caused the stump of a man's leg to become painful from pressure may, if not attended to, also cause the skin of a horse to exhibit a sitfast. An awkward horseman is the more frequent source of the complaint. There are gentlemen so very energetic as riders that the best of saddles may be readily moved under them. The saddle must be well made indeed which can, under no circumstances, be stirred upon the back to that extent which is required to generate a sitfast. Loose girths will likewise establish the nuisance, and so also may the saddle-cloth whenever it is hastily put on so as to become thrown into a fold when the horse is mounted.