This is generally provoked by the heedlessness of the rider. A horse is "overmarked," as the condition is technically called, when the animal is urged onward to the point of falling. The person who may occupy the saddle then becomes conscious of a strange and loud noise coming from the body which he strides; it appears to the equestrian as though some demon were located within the carcass, and were violently striking the sides. Should the indication be observed, the noise will be found to proceed from behind or immediately under, rather than from any part anterior to the rider. [Illustration: THE YOUNG GENTLEMAN AND THE OLD HORSE.] The noise is produced by =spasm of the diaphragm=. The horse must, as the word "overmarked" seems to imply, have been pushed far beyond the point where man should have pulled the rein. A little distance farther, after the symptom is developed, will bring the animal to the ground; let the check, therefore, be immediately given; the rider should dismount; the loins be covered with the gentleman's coat, if nothing better be at hand; he who has caused the misery is bound to make any sacrifice for its alleviation. The girths should be loosened, the bridle removed, and when time has passed for the system to become slightly tranquilized, the sufferer should be very gently led to the nearest shelter. So soon as it is under cover, the following drink should be administered, but time should be taken to give the medicine, as the condition of the horse forbids all haste:-- Sulphuric ether Two ounces. Tincture of camphor Half an ounce. Tincture of opium One ounce. Cold water or gruel One pint. This should be repeated every quarter of an hour, till four drinks are swallowed; then the intervals should be lengthened to half an hour, and, as the symptom decreases, the medicine ought to be administered at still longer periods, and ultimately, but gradually, withdrawn. There are, however, other things to be done. When the animal is first brought in, procure five quiet assistants; give a leg-bandage each to four of the helpers, and a sponge, with a basin of cold water, to the fifth. Order the men to perform their ministration silently; the four are to bandage the four legs while the fifth sponges out the mouth, nose, eyes, and anus; this done, the body is to be superficially cleaned. Sweat is to be removed and dirt taken off; the ears pulled, and the head made comfortable; the tail and mane having been previously combed, a hood and body clothing should be put on.