964 PRACTICE OF AGRICULTURE. Tart III. 



i"i<v, if necessary, by the Join! action of the tongue ami muscles of the check. This arrangement becomes 

 In .1 great measure frustrated In old horses. i>v the superior wear of the inner surface of the upper 



grinders, as well as In the general misapplication of the surfaces of both upper and under teeth, by con- 

 stant attrition, when worn down nearlj to the gums. The unfortunate animal feels sensible of this, and 



endeavours to remedy it by throwing the "car on the outer edge, by an inclination of the lower jaw and 



of the head in general ; and which is so particular in its appearance as to engage the attention of the 



by-standers This defect may be in a considerable degree remedied by casting the animal, and having 



opened and wedged the mouth M a. to keep it SO, removing the inequalities with a well tempered con. 

 rave tile, as much M may he. When the delect is considerable, and the horse is mild and quiet, it is 

 better to file the inequalities CTery day, which will gradually but effectually wear them down. It how. 

 ever happens, that the inclination thus to wear is commonly resumed, and gradually the same loss of 

 nutriment takes place: in which case, soft moist food, as carrots, mashes, soiling, or grazing, must be 

 Substituted for harder substances, and if corn he actually necessary, let it he bruised. Whenever an old 

 horse betravs svmptoms of want of condition, or weakness, and emaciation, that neither his mode of 

 feeding, hit his ratio of work will account for, and particularly if whole grains should he found in his 

 dung, Ins teeth should be examined carefUUy. '1'his undue wearing of the teeth occasions another evil 

 often, which is ulceration of the cheeks, by reason of the projecting ragged surface of the uneven teeth, 

 which can only be remedied by the removal of such portions. These projecting j>ortions are called by 

 farriers wolves' teeth, 



Subsf.ct. 2. Bony Anatomy of the Trunk. 



6306. The trunk of tlie skeleton consists of the spine, the pelvis, and the thorax or 

 chest, composed of the ribs and sternum. 



6.507. The bony column called the spine is made up of seven cervical, eighteen dorsal, six lumbar, and 

 Ave sacral vertebra, with the addition of thirteen or fourteen small tail-bones. The spinal bones are 

 thus divided on account of the varieties they present ; they have, however, some characteristics in com- 

 mon. Each is composed of a spongy bony body, with protruded points called processes, which processes 

 unite, to form a hollow through which the spinal marrow is transmitted ; and by some of these processes 

 the vertebra arc articulated with each other, as well as by their bodies, by which their strength as a 

 column is much increased. Though but little motion exists between any two vertebras, yet the flexibility 

 of the whole spine is considerable. 



6308. The cervical or neck vertebra? [g, h) are called, by farriers and butchers, the rack bones. It is 

 remarkable, that, let the neck be long or short, the number of bones is the same in most quadrupeds. 

 The tir-t and second differ from the rest in figure, and present some other peculiarities. The first is the 

 only one of them to which the great suspensory ligament of the neck does not attach itself, which would 

 have interfered with freedom of motion. It articulates with the second by receiving its tubercular pro. 

 cess within it, and from which process the second of these bones has been called dentiita. Between these 

 two neck bones is situated a part, where the spinal marrow is exposed from any bony covering ; at which 

 part butchers plunge a pointed knife into what they call the pith of the neck, when they want to kill their 

 animals instantaneously, and without effusion of blood ; whence it is called pithing. The remaining five 

 neck bones are not very dissimilar from each other. 



6.509. The dorsal vertebra! {>/} are now and then, though rarely, nineteen in number ; they do not differ 

 materially from each other, but in the length of the spinous processes of the first seven or eight. It is to 

 these elongated spines that we owe the height of the withers; and as the intention of these parts seems 

 principally to serve as levers for the muscles of the back inserted into them, so we can readily understand 

 why their increased or diminished height is favourable or unfavourable to progression. These like the 

 former articulate with each other by processes, as well as by the anterior and posterior surfaces of their 

 bodies ; between each of which is interposed a substance, semi-cartilaginous in its structure, which is most 

 compressible at its sides, these permitting the motion of the spine. 



6310. The six lumbar vertebra? differ from the foregoing in having a longer body, and very long trans- 

 verse processes to make up for the deficiency of ribs in the loins. These bones often unite by the pressure 

 of heavy weights, ami sometimes spontaneously by age, and thus we need not be surprised at the stillness 

 with which some old horses rise when down. 



6.31 1. The five sacral vertebra? (z) are united into one to give strength to the column, and to serve as a 

 fixed support to the pelvis, or basin, with which it is interwedged. From this detail it will appear how 

 admirably this spinal column is adapted to its important functions of serving as a flexible but powerful 

 support to the machine; and how by the formation of a large foramen within the substance of each 

 vertebra?, a bony canal is offered for the safeguard of the spinal marrow, from which, through lateral 

 openings in these vertebra-, the spinal nerves are given off in pairs. The pelvis or basin \2) is composed of 

 the sacrum, the two ossa innominata and coccygis. The dssa innominata in the foetal colt before birth 

 are each composed of the ilium, the ischium, and the pubis, all traces of which division are lost before 

 birth. The ilium is the most considerable, and forms the haunches by a large unequal protuberance 

 which, when very prominent, occasions the horse to be called ragged-hipped. The next largest portion 

 is the ischium or hip bone, on each side. It forms a part of the cotyloid cavity, or cup for the thigh bone, 

 and then stretches back also into a tuberosity which forms the points of the buttocks. The pubis or share 

 bone is the least of the three : in conjunction with the former it forms the acetabulum or cup-like cavity 

 in which the head of the thigh-bone lodges. The pelvis or basin is attached to the sacrum by ligaments 

 of immense strength ; but it has no bony union, by which means, as in the fore extremities, some play is 

 given, and the jar of pure bony connection is avoided. The dssa cuccygis, or bones of the tail, vary from 

 eight to sixteen, but are very commonly thirteen or fourteen. 



6 IIS. The thorax or chest comprises the sternum or breast bone, and the ribs. The sternum («•) of the 

 horse is inclined like the keel of a ship, to which the ribs are attached by strong ties. The rSts Ux) are 

 usually eighteen to each side, of which eight articulate with the sternum, and are called true, while the 

 rem. lining ten, uniting together by intervening cartilages, are called false ribs. The centrals are the 

 longest, those anterior, as well as posterior, are less so: the first is placed perpendicularly, the second 

 less so ; and their obliquity, as well as dimensions, increase as they advance, so as to enlarge the chest to 

 in almost 1 ircular form, which is the most desirable ; but when they are less arched, the belly partakes 

 of the defect, and a H.it-sided horse is commonly a bad carcascd one also. 



Subsect. 3. Bony Anatomy of the Extremities. 

 6313. An examination of the bony ports of the limbs excites our admiration at the 

 wonderful mechanism displayed in their formation: osseous portions also present them- 

 selves, which may be regarded as principally subservient in keeping up that vast chain of 

 continuity and similarity observable throughout Nature's works. In the following ex- 

 planation we shall have occasion to notice several of these. 



6314. The scapula or shoulder blade (He, I), is a broad, flat, and rather triangular bone. It is very unlike 

 the human scapula, having neither acromion, coracoid, nor recurrent process : neither is its situation at 

 all similar to the human blade bone applied to the back ; for, in this instance, the horse may be said to 



