Fecundation of the hybrid female by the male ass or the stallion is not very rare; but it is otherwise with the male hybrid, no instance being recorded in which he has been prolific, though physically the animal appears to be perfect, and often exhibits an intense ardour for the female. The female mule, when fecundated, seldom reaches the natural term of pregnancy, and rarely brings forth a living offspring. The duration of gestation in a mare impregnated by the ass is a little longer than in impregnation by the stallion,— the average being 375 days. Abortion readily occurs, and more care is necessary than in breeding horses or asses.

In breeding mules the choice in the male parent is limited so far as shape is concerned, as the best-formed asses have, relatively to their height, the head too large, short neck, sides too flat, low shoulders, narrow croup, thin arms and thighs, and very narrow hoofs. To obtain well-shaped mules, therefore, the selection of the mare is of the greatest importance in remedying the defects of the sire. Mares with a small head, round body, short back, wide chest and muscular croup, large thighs and arms, a long neck well set-on, and wide round hoofs are the best. Height is not of so much moment, but a mare measuring from 14 to 15 hands high is preferable. A good height for the male ass is between 13 and 14 hands. Mules inherit to an extraordinary degree the shape and peculiarities of the sire; from the mare they derive size, but rarely her bad shape or unsoundnesses. This is fortunate, for, though it is always desirable to breed from sound well-formed stock, yet mares so unsound or defective in shape as to be disqualified for horse-breeding may be utilized for mule-breeding.

The mule foal is not so strong on its limbs as the horse foal, and it does not grow so quickly. It is longer in reaching maturity, for it is of little use under four years of age; but it is useful for a longer period than the horse, often working until it is twenty, thirty, and even forty years of age. When full grown the mule is from 13 to 15, and sometimes 16 hands high; but those from 14 to 15 hands are generally preferred.

The mule is endowed with the chief characteristics of its parents. In its short thick head, long ears, thin limbs, small narrow hoofs, short mane, absence of chestnuts (horny growths) inside the hocks, and tail destitute of hair at the root it is asinine; while in height and body, shape of neck and croup, uniformity of coat, and in teeth it is equine. It has the voice neither of the ass nor of the horse, however, but emits a feeble hoarse noise. The most common colour of the mule is a brown or bay-brown,—bay, or bright bay, or piebald being rare; a chestnut tint is sometimes noticed. It possesses the sobriety, patience, endurance, and sure-footedness of the ass, and the vigour, strength, and courage of the horse. As a beast of burden it is preferable to the horse, being less impatient under the pressure of heavy weights, while the skin being harder and less sensitive renders it more capable of resisting sun and rain. It is very frugal, easily fed, and equally good for carrying as for drawing loads; it walks well and steadily, easily traverses the worst roads or paths, will climb or descend a steep mountain, or pick its steps by the side of a precipice, with the surety and safety of a goat. For hot and dry countries, especially those which are mountainous, it is well adapted, though cold and wet regions are not suitable for it.

The mule, like the ass, enjoys an extraordinary immunity from disease. After the campaign in Egypt in 1882 the English horses suffered most extensively and severely from a kind of malarious fever, but the mules were entirely exempt. A similar exemption has been noticed during the prevalence of epizootic maladies at other times. Nevertheless those diseases which attack the mule (and the asinine species) run their course with great rapidity; for example, glanders, which often appears in a chronic form in the horse, is most acute in the mule and ass. These are also very liable to tetanus from trifling injuries.

The mule has been in use from very early times; the inhabitants of Mysia and Paphlagonia are said to have been the first breeders. With the Greeks and Romans, the latter especially, the mule was much valued for its good qualities, being employed to draw carriages and carry loads. At the present day it is extensively used in nearly every part of the world, in some countries almost supplanting the horse, while for military purposes it is undoubtedly the best transport animal.

The principal mule countries in Europe are the south of France, Spain, Portugal, and Italy, where they are used for pack and draught. The French mules are most numerous on the borders of the Pyrenees, in Gascony, and in Poitou. In Spain mules are used in the Catalan provinces, in the mountainous districts of Andalusia, and in the province of Alicante. Good draught-mules are bred in La Mancha and in the districts on the slopes of the Pyrenees, where they are employed to carry loads. But in Spain, Italy, and some other countries they are also extensively used in carriages; in Spain particularly, where large, fine mules are bred for this purpose, a pair of these animals will often cost more than a pair of horses. The mules of Asia Minor, Syria, Cyprus, Egypt, and Algeria, as well as those of the district between the Tigris and the Persian frontier and in North China, are good. In the Punjab provinces of British India many excellent mules are bred, breeding being largely promoted by the Government. Good mules are reared in North and South America, the principal districts for breeding them in the United States being Kentucky, Missouri, and Kansas. The Kentucky mules are well shaped and showy, being derived from nearly thoroughbred mares known as Kentucky trotters, while those reared in Missouri are hardy, and can endure much privation and hardship. The Mexican mule, bred by a male ass out of a mustang mare, is also a very hardy, strong, and useful animal.

France is perhaps the most important mule-raising country in Europe, four centres being more particularly devoted to this kind of industry: Poitou, the mountainous districts of central France, the Pyrenees, and Dauphiné. The mules of these different parts chiefly differ in height; those of Poitou are large, powerful, and long in the body, and are mainly exported to the departments of Languedoc and Provence, as well as to Spain, Italy, and America; those of Dauphiné are of medium height, with a short, thick body; while those of the centre and the Pyrenees are lighter and smaller, but more active.

Mule-breeding in Poitou is one of the most important branches of industry, and is supposed to date from the time of Philip V. of Spain, when the particular breeds of horses and asses were imported into that region and Gascony. But there is evidence to show that so early as the 10th century the mules of Poitou were of excellent quality. Though this industry has for a number of years been in a most flourishing condition, this has not always been the case; more than a century ago it was the object of violent attacks, and, had it not been for the great advantages the breeders derived from it and the comparatively small expense incurred in carrying it on, it must have languished or ceased altogether. The Government could not understand why so many mares should be lost to horse production and kept to breed mules alone; and in 1717 the intendant-general of the haras went so far as to prohibit male asses being put to mares measuring more than 12 hands from the withers to the top of the hoof under penalty of a fine and confiscation of the ass; and the minister Bertin issued a decree to the effect that all the male asses in Poitou were to be castrated. It was only at a recent period that the haras administration ceased to oppose mule-breeding, when it found that it could not be successfully suppressed; for, while in the one department of Deux-Sèvres 13,000 mares were employed in mule production in 1816, fifty years afterwards there were 23,000. Besides, it was discovered not only that this industry added largely to the national wealth but that mules were extremely useful in the army as pack animals, as well as for draught, especially for mountain artillery.

The Poitou mules are large, and strong enough to be used for heavy draught; those produced elsewhere in France, especially in Gascony, are light and better adapted for weight carrying. In Poitou at the present time about 50,000 mares are kept for mule production; of these it is estimated that 38,000 are bred from every year, and of the produce 18,000 are sold annually. In the fairs of Poitou some mules fetch the large price of 1300 to 1500 francs, and many are sold for 900 or 1000 francs. If the average price be fixed at only 600 francs, it will be seen that Poitou alone realizes annually from its mulebreeding no less than 10,800,000 francs. The statistics of 1840 give the number of mules in France at 373,841, of 1852 at 315,331, of 1862 at 330,987, and the census of 1866 at 345,243. The average price of a mule in 1840 was reckoned at 172 francs, in 1852 at 183 francs, and in 1862 at 278 francs. The total value of the mules in 1840 was estimated at 64,284,246 francs, in 1862 it had increased to 92,078,458 francs. The total amount of revenue derived from the trade in mules was: in 1840, 21,244,148 francs; in 1852, 87,548,310 francs; and in 1862, 162,341,162 francs. Since the last-mentioned date it is probable that there has been a further increase.

In the United Kingdom mules are seldom bred, and their services do not appear to be much appreciated; hence their importation is almost nil. After the war in Egypt in 1882 a large number of mules which had been purchased by the British Government for that campaign were brought to England and sold by public auction, but the average price realized was probably not more than one-half the amount they had cost in the countries in which they were originally purchased.

Mules have in recent times been largely employed in British campaigns, as in the Crimea, India, Abyssinia, South Africa, and Egypt. In the Abyssinian campaign more than 10,000 pack-mules were obtained from Cyprus, Brindisi, Malta, Smyrna, Gibraltar, Alicante, Valencia, Scanderoon, and Beyrout. The order in which these places are enumerated indicates the relative adaptability of the mules for pack transport during that campaign.

During the Zulu war, South-African or Colonial, South-American, North-American, and French mules were employed; but of these the South-African and South-American were found to be the most suitable.

In India mules form part of the permanent transport of the Punjab irregular force, and are used as pack animals in the mountain batteries. They have also been largely used for transport in the many expeditions which have taken place on the north-western frontier. During the recent Afghan war it was proved that for mountain warfare the mule was by far the best beast of burden; and the director of transport with the Indian division during the late Egyptian campaign reported highly of the work done by the Punjab mules, which are somewhat famed for undergoing a great amount of exertion on little food. The breeding of pack-mules, as also of those adapted for batteries of mountain artillery, too much neglected hitherto, is now much encouraged by the Government of India, which supplies many good male asses to different districts free of charge. These asses are chiefly Arab, Spanish, French, and Italian; but very good animals are at times obtained from Bokhara. By stimulating the breeding of improved asses an increasing supply of good sires and mules is obtained.

The experience of British and other European armies in favour of the mule has been corroborated by that of the United States. In the quartermaster-general’s report for 1865 it is stated: “The experience of this (secession) war has convinced all officers of this department that for the army-trains mules are much superior to horses, and of late the horses have almost entirely disappeared from the trains, being transferred to the cavalry or artillery and replaced by mules.”

Mules are well adapted for the sick or hospital transport of an army in the field as pack animals, being smaller, surer-footed, and shorter-paced than horses; but they should be specially selected and trained for this purpose, animals of sufficient strength and docility being necessary. A loaded mule will walk a little more than 3 miles an hour, though the pace will much depend upon the roads. The pace is slow moving down hill, quick up hill. Mules sleep from three to four hours in the twenty-four, the soundest sleep being towards dawn. The male mule can carry more weight than the female, though the latter is steadier for work, being more docile; male mules are often vicious and carry loads badly, so that to render them more tractable they are sometimes castrated. For saddle purposes those which more resemble the horse than the ass are preferable.

The carrying power of the mule varies according to a variety of circumstances from 100 lb to 300 ∏>, the average being about 200 lb including the pack-saddle. In a journey made in 1856 from the city of Del Norte to Chihuahua and Durango in Mexico, a distance of about 500 miles, it was found that out of a train of seventy-five mules the most it was possible for any mule to carry was 27 5 lb; not more than twenty mules could convey more than 250 lb, the average weight carried by the whole train being a little less than 200 lb. The distance per day was about 15 miles. In another journey it was noted that some of the very best mules, out of a very superior description specially selected, which were loaded with 300 lb, gave out completely at the end of two weeks. In the Abyssinian expedition the load had to be reduced to 100 lb, not including the pack-saddle. It has been stated that a good compact mule, when well trained, properly fitted and handled, will carry in ordinary field service 30 per cent, of its own weight. If the load is in proportion to the size of the animal, small mules have the advantage. A 600 lb mule is quite as good for a 200 tt> load as a 900 lb mule is for a 270 lb load.

During the Peninsular War mules were hired by the commissariat for a Spanish dollar a day and rations for the driver. The weight of the load was fixed at 200 lb, and the length of journey in a mountainous country with bad roads was from 10 to 12 miles loaded, 15 to 16 unloaded. The maximum price paid for mules purchased for the Bhutan (India) expedition was 180 rupees; those purchased at Baghdad and Bushire for the Abyssinian expedition averaged 124 rupees 8 annas, in Syria about £20. The mules purchased in the Punjab for the same expedition cost 225 rupees each; those procured in Egypt about £26 10s. per animal. The mules purchased in New York for the Zulu war cost £42 per head, though good serviceable mules can be bought at St Louis for from £25 to £30. A firm in London at the-same time tendered to supply mules from Spain at £35 each for pack, and £37 10s for draught. The South-African mules bought during the Zulu war cost on an average £23 each.

It has been observed that large mules are not so durable as medium-sized ones, especially for military service. In Algeria it was rare to find a mule over 14 hands more than fifteen years of age, and those approaching 15 hands died younger, while those between 13 and 14 hands were frequently more than twenty years old. The older animals were very often mares. (G. FL. )