22 SEATS AND SADDLES. 



fixed on with, one screw each, so as to allow them 

 to be moved either to front or rear, but sufficiently 

 tight to retain them in the position in which they are 

 placed. A small weight is then placed exactly on the 

 centre point of the board at p, the four legs being ad- 



c b 



^-^ /* 



d 



Fig. 1. 



justed square, as at x x x x. If the weight be not 

 so heavy as to overcome the slight friction of the heads 

 of the screws, the board will remain in its position 

 that is, it will stand ; but if it be removed towards one 

 end of the board, say to p\ it will cause the board to 

 turn on the screwheads, and, if not prevented, slide 

 down towards /; but if the two legs at this end be 

 bent backwards to x 1 x 1 , the board will support the 

 weight as before. In like manner, if the weight be 

 removed in the other direction to p*, the legs being 

 square, the same thing will occur, and the board will 

 turn on its legs and slide down towards h, which, how- 

 ever may be prevented by adjusting the same pair of 

 legs as before, and which here represent the hind legs 

 of the horse, to the position x* x?, and in both these 

 cases the board will assume a slanting position, in which 

 the end a b will be lower. Or, the weight being at 

 p 2 , the- board may be made to stand by adjusting the 

 other pair of legs, representing the horse's fore legs, to 



