THE LEVER, THE BIT AND CURB, ETC. 165 



equal to 5 to be applied to the reins, it may, in con- 

 sequence of various arrangements of the mouth-piece 

 and curb, be made to exercise an amount of painful 

 pressure as at A, where 3 parts act on the curb and 

 only 2 on the mouth, which will make the horse bore 

 into the hand ; or as at B, where 3 parts act on the 

 mouth and only 2 on the curb, so that 1 really remains 

 available. Whereas, by reducing the painful action of 

 the curb to 0, as at C, we find that the whole amount 

 of action may be applied to the mouth, and therefore 

 itself reduced to 2. 



Here we have a key to the whole theory and practice 

 of bitting, and there is no difficulty in understanding 

 that its immediate consequence will be to render bits 

 of small dimensions equally efficient and much more 

 certain and reliable in their action than the monstrous 

 pieces of ironmongery usually manufactured and sold 

 ever can be : and we now proceed to enter into further 

 details. 



The first question that naturally presents itself is 

 the absolute length of the lever that is to say, of the 

 upper and lower cheeks of the bit taken together ; the 

 next, that of their relative proportions to each other. 

 Before going into the consideration of these it will be 

 well to clear up one or two preliminary matters, merely 

 premising what is self-evident on inspection namely, 

 that a bit may be regarded as a pair of levers connected 

 together by the mouth-piece. At first sight this might 

 lead to the conclusion that the centre of the rivet on 

 each side is always the point from which the length of 

 the upper and lower bars is to be measured. This is, 

 however, only true for those forms of mouth -piece which 

 consist of a port and two lateral straight portions ; but 



