106 



THE HORSE. 



eated in the cut wD be sufficiently apparent before the jaws are locked, 

 and while medicine can be administered with tolerable ease. 



The jaws are unnaturally fixed, and then he observes that there is a 

 stiffness of the neck, a difficuliy in bringing ihe head round, and a promi- 

 nence, and hardness, and unyieldingness of all the muscles of the neck, 

 with an unusual protrusion of the head. It next occurs that the poor ani- 

 mal cannot bend his head. The retractor muscle (fig. g, p. 98) is affected 

 by spasm, and the eye is drawn into the socket — squinting outward — and 

 tlie haw protruding over a portion of it. The nostril is expanded, the ear 

 erect, and the countenance anxious ; — the back and loins are stiff, and if he 

 is turned in his stall, the whole body turns at once like an unbending piece 

 of wood. The muscles of the belly are also affected by spasm, and he is 

 tucked up (his belly contracted and drawn up) to a strange degree. The 

 tail is erect, and constantly quivering. The extremities are singularly 

 fixed; — the hind-legs straddling ; — the fore-legs projecting forward and out- 

 ward (as some one has aptly described it) like the legs of a stool. The 

 pulse at first not much affected, but soon becomes quick, and small, and 

 irregular ; the breathing more laborious as the disease proceeds, and the 

 countenance wild and haggard, and expressive of extreme agony. The 

 pain which attends the cramp of one limb will enable us to judge of that 

 which must accompany universal spasm. If a person goes near the horse, 

 or touches him in the slightest way, although he may be unable to move, 

 yet the sudden quickening of the pulse will tell what the animal feels 

 and fears. So the disease goes on for nine or ten days, until the animal 

 is exhausted by the expenditure of nervous energy, and the continuance 

 of torture. 



If, from strength of constitution or medical treatment, he should recover, 

 the first favourable symptom is a slight and short remission of the spasm ; 

 the time of remission gradually lengthening, and the jaws a little relax- 

 ing ; but the progress of cure is exceedingly slow, and the horse is left 

 very weak. 



Tetanus is evidently an affection of the nerves. A small fibre of some 

 nerve has been injured, and the effect of that injury has spread to the 

 origin of the nerve ; the brain has become affected, and universal diseased 

 action speedily follows. Locked-jaw generally arises from a wound, and 

 oftenest a wound of a tendinous or ligamentous part ; but depending not 



