162 BITS AND BITTING. 



mechanical advantage obtained is proportionate to the 

 relative length of these two arms. Thus, if P F, Fig. 9 

 (a), be equal twice W F, a power equal 1 applied at P 

 will counterbalance a weight equal 2 applied at W; 

 but, as regards our purpose, it is more especially necessary 

 to observe that the power and the weight move in 



J s . f order P 2 F. J\v 



2* order 



Fig. 9. 



opposite directions, or rotate round the fulcrum or prop, 

 as is shown by the direction of the arrows. Applying 

 this to a bit, the cheeks of which represent the lever, 

 there can be no question as to where the power is applied, 

 being the lower ring to which the rein is attached, 

 nor as to the direction in which it is intended to act, 

 being towards the rider's hand ; and if a bit act as a 

 lever of the 'first order, the fulcrum or prop must be 

 represented by the bars of the horse's mouth on which 

 the mouth-piece acts, and the pressure of the curb' 1 ' on 

 the chin would necessarily represent the weight to be 

 raised. But it has been shown that, in levers of the 

 first order, the power and weight move in opposite 

 directions in their rotation about the prop ; in this case, 

 therefore, the horse's chin, in consequence of the pressure 

 exercised by the curb, should move forward that is 

 to say, away from the rider's hand ; and the greater 

 the lever-power of the bit, and the stronger the pull on 



* We use the word curb for curb-chain, and bit or curbed-bit 

 for what is sometimes called curb. 



