The six species of this genus are the horse, ass, common zebra, zebra of the plains, quagga, dzhiggtai, with the mule, which may be regarded as a sub-species.
Of all quadrupeds, the horse possesses, along with grandeur of stature, the greatest elegance and proportion of parts. By comparing him with the animals above or below him, we find that the ass is ill made, and that the head of the lion is too large; that the limbs of the ox are too slender, and too short in proportion to the size of his body; that the camel is deformed; and the grosser animals, as the rhinoceros, hippopotamus, and elephant, may be considered as rude and shapeless masses. The great difference between the head of man and that of the quadruped, consists in the length of his jaws, which is the most ignoble of all characters. But, although the jaws of the horse be very long, he has not, like the ass, an air of imbecility, nor, like the ox, of stupidity. The regularity and proportion of the parts of his head, give him a light and sprightly aspect, being gracefully attached to his finely arched neck, which is well supported by the beauty of his chest. He elevates his head, as if anxious to exalt himself above the condition of other quadrupeds. In this noble attitude he regards man, face to face. His eyes are open, lively, and intelligent; his ears handsome, and of a proper height, being neither too long, like those of the ass, nor too short, like those of the bull. His mane adorns his graceful neck, and gives him the appearance of strength and courage. His long bushy tail covers, and terminates with advantage, the extremity of his body. His tail, very different from the short tails of the deer, elephant, and hippopotamus, and from the naked tails of the ass, camel, and rhinoceros, is formed of long, thick hairs, which seem to rise from his crupper, because the trunk from which they proceed is very short. He cannot, like the lion, elevate his tail; but, though pendulous, it becomes him better; and as he can move it from side to side, it serves him to drive off the flies, which incommode him; for though his skin is very firm, and well garnished with close hair, it is, nevertheless, very sensible.
Brown says, the head of the horse should not be too long, and it ought to be rather thin than otherwise. The front should be narrow, and a little convex; the eye-pits well filled, and the eye-lids thin; the eyes large and prominent, clear, lively, and sparkling with fiery glances; the pupil should be large; the under jaw should be a little thick, but not fleshy; the nose slightly arched; the nostrils open and deep, and divided by a thin septum or partition; the ears should be small, erect, and narrow, but not too stiff, and placed on the upper part of the head, at a proper distance from each other, but not too wide, as this always gives a horse a disagreeable aspect; the mouth should be delicate, and moderately split; the withers sharp and elevated; the shoulders flat and not confined; the back equal, a little arched lengthwise, and raised on each side of the spine, which should have the appearance of being slightly sunk; the flanks short and full; the crupper round and plump; the haunches well furnished with muscular flesh; the dock, or fleshy part of the tail, firm and thick; the thighs large and muscular; the hough round before, broad on the sides, and tendinous behind; the shank thin before, and broad on the sides; the tendon Achillis prominent, strong, and well detached from the leg-bone; and the fetlock somewhat prominent, and furnished with a small tuft of long hair behind; the pasterns should be of a middling length, and pretty large; the coronet a little elevated; the hoof black, solid, and shining; the instep high; the quarters round; the heels broad, and a little prominent; the frog thin and small, and the sole thick and concave.—Vide Arabian—Hunter—Roadster, Race Horse, &c.
The horse is considered to have been originally a native of what is called the old world, and by the industry of man to have been planted in the new. It appears from the sacred records, that his subjugation did not take place until many years after that of the camel and the ass.
At what precise time foreign horses were brought into Britain is uncertain; but it is not improbable that it was a very early one, since history informs us they were sufficiently numerous, and their uses well known, when Julius Cæsar invaded the island. Whether these early horses were the entire produce of Britain, or whether they had already been mixed, it is likely that their intercourse with the Roman cavalry would introduce new races, as diversified as the countries from whence the Romans themselves drew their own immense supplies. Freed from their conquerors, the English cultivated the arts of peace, and were consequently not unmindful of the horse, which was become, as early as A.D. 930, so valuable that Athelstan prohibited their exportation.
William the Conqueror brought with him the means of greatly improving the island horse; and the barons who accompanied him, being spread over the kingdom, in their newly acquired estates, rapidly diffused a valuable mixture among the native breeds. One of these nobles (Roger de Belesme, Earl of Shrewsbury) is particularly celebrated for introducing Spanish stallions into his Welsh possessions.
In 1121, the first Arabian horse on record was imported into England, and the crusades, which soon succeeded, were the means of introducing a large accession of eastern horses from the Levant. The traffic in horses now began to assume much of its future character: Smithfield was established as a horse-market; and the dealing in this animal was already become a regular profession, as well as already garnished with much of its trickery.
To Edward the Second the breed of English horses owes much of its early improvement: he procured cavalry horses from Lombardy, Italy, and Spain, and heavy draught horses from Flanders. From this time the public attention appears to have been particularly directed to the necessity of improving the breed of horses; and many public ordinances were promulgated to that effect. In the reigns of Henry VII. and VIII. it became common to import foreign stallions for this purpose from Barbary and Spain; and, in the two following reigns, others were imported from Belgium, Flanders, and Denmark; and as the former were intended to improve the speed, spirit, and beauty, these latter added greatly to the size of the future breeds. As early as the twelfth and thirteenth centuries, there were horse-races in England; but these appear to have been principally confined to trials of speed and continuance over uncertain grounds between native horses. In the reign of Henry VIII., horses either procured from Barbary, or bred from such, were expressly used for this purpose; and we may date the systematic improvement in the breed, by the admixture of what we call blood, to have its origin about this time.