154 



MAMMALIA. 



weights. They cannot, however, be profitably reared 

 in a domesticated state, and therefore the use of them 

 is necessarily restricted to a very limited space in 

 the vicinity of their native forests. In the peculiar 

 style of walking, both of camels and of elephants, at 

 their usual moderate pace, at which they can continue 

 for a considerable time without rest, we see examples 

 of one of the disqualifications for labour in animals 

 which are not deficient either in size or in strength. 

 It will readily be understood that every motion which 

 deflects the centre of gravity of the body of an animal 

 from the straight line of its march, whether the deflec- 

 tion be right and left or up and down, increases the 

 labour of the animal by the burden of its own weight 

 carried over the whole measures of those deflections. 

 Thus for instance, if the step of a camel in its slow 

 march is two feet and a half (the actual measure is a 

 matter of no consequence), and the dodging raises 

 the centre of gravity three inches at the one part of 

 the step, and moves it three inches laterally in the 

 other part, then in addition to the step of thirty inches 

 it has carried its own body six inches in absolute 

 space, and the straining and new momentum necessary 

 to be acquired at every turn may be reckoned at four 

 inches more. By means of this constant moving of 

 the centre of gravity, therefore, such an animal must 

 exert one-third more strength in order to get over the 

 ground than an animal which carries the centre of gra- 

 vity forward in a direct line. The loss must be the 

 same in the case of the load which it carries as in 

 that of its own body ; and therefore, even as beasts of 

 burden, camels work at a very great disadvantage, 

 both in respect of their own bodies and in that of the 

 burdens which they can carry. The disadvantages 

 in the case of the elephant are probably not less, but 

 the great strength of the elephant, and the fact of its 

 being employed chiefly in cases where show is the 

 object rather than economy, do not bring it within the 

 limits of ordinary calculation. 



None of the toed animals are of sufficient size for 

 being employed as beasts of burden, or for purposes 

 of draught, except for very light weights, or in such 

 numbers as to be inconvenient in thickly inhabited 

 countries. Dogs are indeed used for drawing trucks 

 and other light carriages, and they are the animals 

 exclusively made use of by the Esquimaux for draw- 

 ing their sledges over the snow. They are much 

 more hardy and less subject to fatigue than almost 

 any other animals ; and at their common walking or 

 running pace, in which the elasticity of the spine 

 does not come into action, they are well formed for 

 such weights as they are able to draw. When they 

 run, however, they jerk the body so much up and 

 down by the action of the spine that they are ineffi- 

 cient in short harness. When yoked by long thongs, 

 as the Esquimaux yoke them, they are more effective 

 when put to their speed ; but then the difficulty of 

 getting them to pull together more than counter- 

 balances the advantages derived from the freedom of 

 their action ; and the loss of power in this way ren- 

 ders it necessary to employ more than double the 

 number that would be requisite if they could pull 

 fairly together. We cannot, however, consider the 

 employment of the dog generally as a working animal, 

 as the most economical use of them. The leading 

 character of .the dog, taken in the average of- the 

 breeds, is not his physical strength, but his courage 

 and sagacity taken jointly ; and when he is made 

 a merely mechanical labourer, what ought to be 



considered as his most valuable properties are left 

 unemployed. 



Our field of examination, as to the advantages of 

 the mammalia for mere labour in the service of man, 

 is therefore narrowed to the hoofed animals, and 

 even for general purposes to a few of them. The 

 solid hoof is preferable, as a general base from which 

 to overcome a resistance in traction, to the divided 

 hoof, although as the divided hoof takes a firmer 

 hold on its support, there are some cases in which it 

 deserves the preference. 



Of solid-hoofed animals the horse possesses advan- 

 tages over every other, in beauty of form, in steadi- 

 ness to the line of motion in most of his paces, and 

 in fitness for every description of climate ; and of the 

 animals with divided hoofs the preference must he 

 given to the ox tribe, in their superior strength, doci- 

 lity of manners, and adaptation to climate. We need 

 not go into any details of either of those animals, 

 because every reader has opportunities of observing 

 them for himself. Whoever chooses to observe will 

 perceive that in all the paces of a well-bred horse 

 there is very little swing of the centre of gravity, and 

 that the principal motions are performed by the limbs, 

 and not by the spine. In slow motion the centre of 

 gravity in the ox is also steady, and therefore an ox 

 can take a strong pull in comparison to his weight 

 and strength. Such animals are, however, not well 

 adapted for rapid motion, and consequently their 

 chief use is in the labour of the field, or in the bearing 

 of burdens along difficult roads, in the latter of which 

 respects they are not equal to mules, either in sure-foot- 

 edness or in patience of endurance, and consequently 

 wherever mules can be procured for roads which are 

 too difficult for horses they are preferred. Mules of 

 superior quality cannot be obtained, however, except 

 in comparatively warm countries, because the ass dege- 

 nerates much more from severity of climate than the 

 horse does, and the good qualities of the mule appear 

 to depend much more on those of the ass than on 

 those of the horse. Among the hoofed animals there 

 is a modification of the style of walking, and conse- 

 quently of their organisation as adapted to that style, 

 which is worthy of notice, namely, the difference 

 between galloping animals and leaping or bounding 

 ones. Goats, sheep, and antelopes, and also deer, are 

 all bounding animals that is, they can throw them- 

 selves to a considerable height from the ground, and 

 project themselves to a considerable distance. Such 

 motion is perfectly incompatible with the carrying of 

 riders or burdens, or with drawing in short harness, 

 and therefore none of the animals are used for any 

 such purposes. These naturally, therefore, are left 

 more in a state of nature, or sought for only on account 

 of the substance of their bodies, than the races which 

 have not this bounding style in their rapid motion. 

 The only exception worth notice is the rein deer, 

 which is so effective in drawing the sledges of the 

 Laplanders, and that animal draws in comparatively 

 long traces, and could be but little effective in apply- 

 ing its weight to the rapid traction of a vehicle with 

 shafts. 



Organs of Leaping. The last mentioned ruminant 

 animals, which bound along with incredible swiftness, 

 and rise high and project themselves far in some of 

 the species, are, notwithstanding their agility, and the 

 splendid style of their motions, not strictly speaking 

 leaping animals. Their anterior and posterior extre- 

 mities are nearly of the same length ; and though 



