Practically, therefore, so the heart be diseased, it is of small import what shape the disorder may assume. The death is always sudden; it is likely to occur when the horse is journeying at its topmost speed; when accident generally follows. Consequently, it is perhaps wiser to take the life, thus afflicted and thus dangerous. The horse may appear blooming, may even be skittish; yet, the existence shall at any moment be cut short. Auscultation affords the surest means of detection. Place the ear close to the left side and lower part of the chest; if any unusual sound be audible, conclude the heart to be diseased. The signs visible, externally, are sometimes sufficiently emphatic to admit of no doubt. The eye is expressive of constant anguish; the countenance is haggard; the pulse is feeble and irregular, but the heart throbs; its throbs are visible, and frequently they are to be seen as plainly on the right side as on the left. The beat is occasionally so violent as to shake the body. The carotid artery can be felt to pulsate in the neck. The regurgitation, within the jugular vein, is nearly always excessive,--it often reaches almost to the jaw. It takes place by jerks, which ascend high and higher, each becoming less and more weak, as it mounts upward. An attempt to represent this has been hazarded in the illustration. It is, however, impossible to truthfully depict action; and the reader will comprehend the jerks, in nature, do not occur all at the same period; but the first subsides before the second can be exhibited. The appetite is sometimes ravenous; more often it is fastidious. The breathing is not accelerated, excepting during the existence of pain; lameness is occasionally witnessed in one fore leg; dropsical swellings and abdominal pains have been observed. The animal, when progressing, will suddenly stop, tremble, and appear about to fall; as suddenly, it will recover and proceed upon the journey. Noises, expressive of acute anguish, are, under the impulse of the moment, occasionally uttered. Sometimes the horse cannot be made to move, and it is always averse to turn in the stall. Often it is seen to yawn; but more frequently has been known to heave long and deep-drawn sighs. No ascertained sign, however, announces the climax of the disorder to be near at hand. Death is always unexpected, and, therefore, is a surprise. The cause of heart disease is unknown. It may, however, be surmised from the fact that it is most common in gentlemen's stables, and is all but engrossed by the animals which have for years been subjected to the abuses therein practiced. It is incurable; and all physic is thrown away upon this disorder. CHAPTER VII. THE STOMACH, LIVER, ETC.--THEIR ACCIDENTS AND THEIR DISEASES. SPASM OF THE DIAPHRAGM.