CONSTRUCTION OF CURBS. 85 



5. Thickness of mouth-piece. With the object of having the 

 mouth-piece comfortable to the animal's mouth, I do not think 

 that it ought to be less than two-thirds of an inch in thickness, 

 which is about two inches in circumference. 



6. Outward inclination of upper ends of cheeks. I like Mr. 

 Langham-Reed's idea of giving an outward inclination to the 

 upper ends of the cheeks, so as to accommodate themselves to 

 the shape of the horse's upper jaw. He makes the distance 

 between the tops of the upper ends of the cheeks, one inch 

 more than the width of the mouth-piece. 



7. Size of loose rings. The loose rings of a curb should be 

 sufficiently large (say, not less than i^j inch in diameter) to 

 prevent the rings of a running martingale catching on them, 

 in the event of such a martingale being used on the curb 

 reins. 



8. Prevention of top eyes of curb exerting a downward pull 

 on the head-stall. We have already (p. 80) seen the part 

 played by the length of the upper end of the cheek in this 

 connection. We may further obviate the objectionable pull 

 in question by making the top eyes of such a shape, as in 

 Lord T/ntrlozv's bit (Fig. 55), that they will be able to 

 revolve forward without causing any strain to be put on the 

 head-stall. The Chifney bit (Fig. 53) effects this object in a 

 still more perfect form ; because its curb-chain alone resists 

 the forward revolution of the upper ends of the cheeks. With 

 it, the whole of the pressure on the mouth is taken by the 

 bars, tongue and chin-groove, and none by the animal's poll. 



The downward pull on the head-stall may be removed to a 

 certain extent by having the top eyes of the curb made 

 larger than usual, as in Fig. 96 ; and by connecting them to 

 the cheek-pieces of the head-stall by means of spring hooks. 



A Chifney bit is often objected to, on account of its undue 

 severity, especially when its reins are in the hands of an 

 indifferent rider. If, in such cases, the horse that was over- 



