380 LOCK-JAW, OR TETANUS. 



eye, are more likely in this country than any other injury to 

 cause it. In America, it is not an unfrequent result of 

 castration ; and in some tropical climates compression of 

 the cord in the operation must always be avoided, so apt is 

 any irritation to produce it. It is by many considered as 

 most apt to follow wounds of tendinous and ligamentous 

 structures, but a wound on any part may start it up. 



The symptoms. — If a good physiologist were told that 

 tetanus was a spasmodic contraction of all the voluntary 

 muscles, he would describe the following symptoms without 

 having seen the disease, so exactly are they characteristic 

 of such a state. It may originate from no perceptible 

 cause, or it may be produced by a wound, in which case 

 the part injured has healed kindly, and the opening is nearly 

 closed before this terrible complaint makes its appearance. 

 It commences usually by a certain stiffness about the head, 

 and a peculiar mode of standing. Upon raising the head 

 the haws of both eyes are pushed out, giving to the coun- 

 tenance of the animal a strange expression ; but sooner or 

 later it extends all over the body. By the tetanic action 

 the haw is drawn partly over the globe, at the same time 

 that the tension of other muscles gives the eyes a vivid 

 appearance, which ill accords with the more placid effect of 

 a protruded haw. The jaws are not invariably fixed, though 

 from their being generally closed springs the popular name 

 of the disorder. As the disease extends over the volun- 

 tary muscles of the trunk and extremities, the appearances 

 are distressing in the extreme. The head is raised, the 

 ears pointed forwards, the nostrils dilated, and the nose is 

 protruded. The legs straddle wide, the tail is cocked, and 

 quivers ; and the abdominal muscles are drawn tight over 

 the belly, giving to the horse an appearance of having just 

 completed some extraordinary exertion. The complaint 

 presents a few moments of imperfect relaxation sometimes, 

 from the extreme contractions of over-strained muscles ; 

 while profuse sweats mark the distress of continued con- 

 vulsion. The circulation is, in most instances, at first 

 not much affected ; but as the disease increases, the pulse 

 quickens, and becomes tremulous and irregular. The 

 respiration also gradually becomes hurried and intermittent ; 

 costiveness is usually present, and the urine is sparingly 



