136 BITS AND BITTIKG. 



tongue lies, or tlie distance between the two bars inter- 

 nally, which determines how much of the mouthpiece 

 may be allowed for the port ; the remainder must be 

 reserved for the action on the bars. 



The third dimension is what we term the height of 

 the bars, — that is to say, the distance between a straight 

 edge supposed to rest on the upper surface of the bars 

 at d, fig. 1 2, as above, and another straight edge placed 

 exactly parallel to it, and touching the undermost 

 point of the chin-groove — mathematically speaking, 

 the tangent to the curve formed by the gToove. This 

 latter dimension — the height of the bars — is perhaps 

 the most important of all, because all the remaining 

 dimensions of the bit must be deduced from it. 



The width of the mouth is, as may be supposed, a 

 very variable quantity, depending on the breed and 

 size of the horse. Xevertheless Lieutenant- Colonel 

 von Oeynhausen,* who has had occasion to measure 

 the mouths of a very great number and variety of 

 horses, says,t that with the great majority of horses of 

 the smaller medium size, 15.1 to 15.3 hands high, their 

 dimension amounts to 4 inches. With very small and 

 very light horses one finds occasionally 3J inches ; the 

 great majority of good-sized saddle-horses, 15.3 to 16.2 

 hands, have 4J inches, and some very large ones go to 

 4:\ inches ; while 5 inches is only to be found amongst 

 very heavy draught animals : and on reducing these to 

 English measure we have 4.148, 3.889, 4.407, 4.797, 

 and 5-185 English inches. 



* Of the Austrian army — perhaps the most learned man liv- 

 ing in the matter of horse-flesh, and the author of several ad- 

 mirable works. 



t 'Zaumungs Lehre,' p. IP. 



