MECHANISM OF DRAUGHT. 



77 



sidered. We may, however, take for granted that the comparative 

 weight which would be an advantage to a heavy draught-horse in a 

 city Hke London, would be a decided drawback to the efficiency of a 

 cart-horse that had to do his work on arable land, especially if it was 

 rough, like on "ridge and furrow" ; because the raising of his weight 

 at each step, would entail far greater muscular exertion, than if his 

 labour was on a smooth road. Sanson {Traitc de Zootechnie) considers 

 that about iioo Its. is the best weight for a horse of light draught, and 

 that the heavy cart-horse should not weigh more than 1,760 lbs. {800 

 kilogr.) and not less than 1,540 lbs. (700 kilogr.). 



2. The cart-horse ought to have a heavy neck as well as massive 



Fig. 49. — Mechanism of Draught. (From Colin's PJiysiologic Coinparcc.) 



shoulders. As a natural corollary to this proposition, which' infers the 

 lowering of the head and neck, we must condemn the constant use of 

 bearing reins with the class of horse which we are now considering. 



3. The shoes of the horse should have toe-pieces when the ground is 

 favourable to their employment. 



4. The fore-hand should be light and the head carried high, when 

 the horse, on account of the slippery nature of the ground, is unable 

 to use his fore legs, except to a very slight degree, as propellers. Thus, 

 the weight has to be kept almost entirely off the shafts of London hansom 

 cab-horses, which would be rendered very liable to fall down on the greasy 

 wood pavement and glass-Hke asphalte, if a fair proportion of the load 

 were to be put on their backs. Not only is weight kept off their backs. 



