164 



BITS AND BITTING. 



bearing that is to say, the line connecting the two 

 points of the mouthpiece which rest on the bars of the 

 horse's mouth does not coincide with the axis of the 

 bit passing through the centre of the two rivets, which 

 must be taken into account in estimating the relative 

 lengths of the upper and lower bars of the bit. See 

 fig. 10. 



Fig. 10. 



The measure for the length of the upper bar of the 

 bit, taken from the " line of bearing " to the point at 

 which the curb-hook acts, is the height of the bars of 

 the horse's mouth, which, as has been shown in a pre- 

 vious chapter, is pretty nearly a constant quantity 

 namely, 1 ^ English inches, decreasing with very small 

 horses and ponies to ly 6 ^ ; therefore, rejecting too great 

 nicety, we may say that If inches is the proper length 

 for the upper bar very seldom less, and hardly ever 

 more. 



It would be very easy to demonstrate mathematically 

 why these two dimensions should always correspond, 

 but we prefer the simpler and more obvious way of 

 showing what the consequences of a departure from 

 the rule must necessarily be. 



If one puts a bit into a horse's mouth without attach- 



