THE SPINE AND BACK. 171 



Qiein for labour when quicker and fuller respiration is required. At all events, a tight 

 girth, though an almost necessary nuisance, is a very consideraole one, when all the 

 exertion of which he is capable is required from the horse. Who has not perceived 

 the address with which, by bellying out the chest, the old horse renders every attempt 

 to girth him tight comparatively useless ; and when a horse is blown, what imme- 

 diate relief has ungirthing him afforded, by permitting the intercostals to act with 

 greater power ? 



A point of consequence regarding the capacity of the chest, is the length or short- 

 ness of the carcase; or the extent of the ribs from the elbow backward. Some horses 

 are what is called ribbed home ; there is but little space (see cuts pp. 68 and 167) 

 between the last rib and the hip-bone. In others the distance is considerably greater, 

 and is plainly evident by the falling in of the flank. The question then is, what 

 service is required from the horse ] If he has to carry a heavy weight, and has 

 much work to do, he should be ribbed home the last rib and the hip-bone should 

 not be far from each other. There is more capacity of chest and of belly there is 

 less distance between the points of support and greater strength and endurance. 

 A hackney (and we would almost say a hunter) can scarcely be too well ribbed 

 home. 



If speed, however, is required, there must be room for the full action of the hinder 

 limbs ; and this can only exist where there is sufficient space between the last rib 

 and the hip-bone. The owner of the horse must make up his mind as to what he 

 wants from him, and be satisfied if he obtains that; for, let him be assured that he 

 cannot have everything, for this would require those differences of conformation that 

 cannot possibly exist in the same animal. 



The thorax, or chest, is formed by the spine/, above (p. 167) the ribs e, on either 

 side ; and the sternum, or breast-bone, c, beneath. 



THE SPINE AND BACK. 



The spine, or back, consists of a chain of bones from the poll to the extremity of 

 the tail. It is made up of twenty-three bones from the neck to the haunch ; eigh- 

 teen, called dorsal vertebrse, composing the back ; and five lumbar vertebrae, occupy- 

 ing the loins. On this part of the animal the weight or burden is laid, and there 

 are two things to be principally considered, easiness of carriage and strength. If 

 the back were composed of unyielding materials if it resembled a bar of wood or 

 iron, much jarring or jolting, in the rapid motion of the animal, could not possibly 

 be endured. In order to avoid this, as well as to assist in turning, the back is divided 

 into numerous bones ; and between each pair of bones there is interposed a cartila- 

 ginous substance, most highly elastic, that will yield and give way to every jar, not 

 so much as to occasion insecurity between the bones, or to permit considerable motion 

 between any one pair, but forming altogether an aggregate mass of such perfect elas- 

 ticity, that the rider sits almost undisturbed, however high may be the action, or how- 

 ever rapid the pace. 



Strength is as important as ease ; therefore these bones are united together with pe- 

 culiar firmness. The round head of one is exactly fitted to the cup or cavity of that 

 immediately before it ; and between them is placed the elastic ligamentous substance, 

 which has been just described, so strong, that in endeavouring to separate the bones 

 of the back, they will break before this substance will give way. In addition to this 

 there are ligaments running along the broad under-surface of these bones ligaments 

 between each of the transverse processes, or side projections of the bones ligaments 

 between the spinous processes or upright projections, and also a continuation of the 

 strong ligament of the neck running along the whole course of the back and loins, 

 lengthening and contracting, as in the neck, with the motions of the animal, and 

 forming^ a powerful bond of union between the bones. 



By these means the hunter will carry a heavy man without fatigue or strain through 

 a long chase ; and those shocks and jars are avoided which would be annoying to tht 

 rider, and injurious and speedily fatal to the horse. 



Thesp provisions, however, although adequate to common or even severe exertion, 

 will not protect the animal from the consequences of brutal usage ; and, therefore, if 

 tho horse is mu^h overweighted, or violently exercised, or too suddenly pulled upon 

 his haunches, these ligaments are strained. Inflammation follows. The ligaments 

 Become changed to bone, and the joints of the back lose their springiness and ease of 



