This term may be employed to describe the apparatus used by veterinary surgeons for casting and securing horses on the ground. It consists of stout leather straps with steel eyes and buckles, and a specially made rope terminating in a few feet of chain, where the principal strength is required (figs. 499 and 500). The subject may be cast on either side or readily turned over, when down, from one to the other. The accompanying illustrations give an idea of the modus operandi of casting (Plate LI). The horse to be cast is first made to stand with all four legs close together; the rope is then drawn up tight, the leading man standing-near to the fore hobble, and at the word of command the three or four men engaged on the rope pull together in an outward and backward direction. To ensure the animal falling on the side opposite to that on which the men are pulling, another rope is usually attached on the falling side to a surcingle or else under the opposite arm, and given into the charge of one who can be depended on to exert the necessary power when the right moment arrives. When down, the rope is prevented from running out, and the horse from moving his legs, by a spring hook (fig. 501) being inserted between one of the links of the shortened chain, while his head is held back and pressed upon the ground. A piece of old pasture is the most convenient and at the same time safest bed upon which to cast animals, but where this is not procurable, a thick bed of straw answers the purpose equally well.
The physiological means of restraint have been incidentally referred to in other parts of this work, notably that dealing with the subject of local and general anaesthesia.
For minor operations cocaine is one of the most valuable of recently discovered anaesthetics. By its aid we may perform minor operations upon the eye, the mucous membranes of the mouth, nostrils, etc. By injecting it under the skin, even such severe pain as that inflicted by firing can be obviated, and the patient made to stand during the operation. A solution containing from 4 per cent to 10 per cent of the drug is commonly employed, whether for painting on a mucous membrane or injecting subcu-taneously, and up to about 15 grains, there is absolute safety. No greater amount should be used at any one time except under professional direction. (See AnAesthesia, Vol. II, p. 479).
Fig. 501. - Spring Hook for Hobbles.