l.A.MENKSS: ITS CAUSES AND TREATMENT. 305 



Our first considei'ntion shoiikl Uo the i)liysiol()«j;y of noiiuiil ov 

 healtliy locomotion, that thence we may the more easily reach our 

 conclusions touchinjr lameness, or that Avliich is abnormal, and hy 

 this i)r(jcess ^ve ought to succeed in obtaining a clew to the sobition 

 of the first problem, to wit, in which leg is the seat of the lameness? 



A woid of ileHnition is here necessary, in order to render that 

 which follows more easily intelligible. In veterinary nomenclature 

 each two of the legs, as referred to in pairs, is denominated a biped. 

 Of the four ]>oints occupied by the feet of the animal while staiuling 

 at rest, foiiuing a sfjuare, the two fore legs are known as the anteiior 

 biped; the two hinder, the posteiioi-; the two on one side, the latenil : 

 and one of either the front oi- hind bii)ed with the opposite leg of 

 the hind or front biped will foiin the diagonal bijHHl. 



Considering, as it is proper to do, that in a condition of health 

 each separate biped and each individual leg is required to pei-foini 

 an equal and uniform function and to carry an even or equal por- 

 tion of the weight of the body, it will be readily a])preciatcd that 

 the result of tliis distribution will be a regidar, evenly lialanced, 

 and smooth displacement of the body thus supported by the four 

 legs, and that therefore, according to the rapidit}'^ of the motion in 

 dilTerent gaits, each single leg will be i-equii"ed at certain succes- 

 sive moments to bear the weight which had rested upon its congener 

 while it was itself in the air, in the act of moving; or, again, two 

 different legs of a biped may be called upon to bear the weight of 

 fhe two legs of the opposite bijied while also in the air in the act 

 of moving. 



To simplify the matter by an illustration, the weight of an animal 

 may be placed at 1.000 pounds, of which each leg, in a normal and 

 healthy condition, supports while at rest 2r)0 pounds. AVhen one of 

 the fore legs is in action, or in the aii', and carrying no weight, its 

 "250 pounds share of the weight will be thrown upon its congener, or 

 l)artner. to sustain. If the two legs of a biped are both in action and 

 raised from the groimd, their congeners, still resting in inaction, will 

 carry the total weight of the other two, or 500 pounds. And as the 

 succession of movements continues, and the change from one leg to 

 another or from one biped to another, as may be required by the 

 gait, proceeds, there will result a smooth, even, and equal balancing 

 of active movements, .shifting the weight fioni one leg or one biped 

 to another, with symmetrical precision, and we shall be presented 

 with an interesting example of the ]ilay of vital inachanics in a 

 healthy organization. 



Much may be learned from the accurate study of the action of a 

 single leg. Normally, its movements will be without variation or 

 failure. When at rest it will easily sustain the weight assigned to it 

 36444"— IG 20 



