192 Bits and Bitting. 



be placed in the horse's moutli like a bit, with the bar 

 a b ^\. exactly the proper point (opposite the chin- 

 groove), the fixed cheekpiece c d being then held gently 

 up to the oiT side of the mouth (the operator facing the 

 horse's forehead), the sliding one ^y* may be shoved up 

 just close enough to the cheek, at the near side, not to 

 displace the lips ; and then fixing it w^ith the screw 

 and removing the gauge, we can read oflfthe dimension 

 of the width of our mouthpiece from the scale engraved 

 on a b. 



The figure shows further a rod g h fitted to slide up 

 and down the movable cheekpiece ef^ which is gradu- 

 ated into inches and eighths or tenths on its lower 

 limb. This contrivance enables us to measure the 

 height of the bar of the mouth, which is done in the 

 following manner : The instrument, adjusted to the 

 proper width of the horse's mouth, is placed as before, 

 with the bar a b exactly opposite the chin-groove, but 

 ti7iderneath the tongue^ and is then wheeled round on 

 its own axis till the upper limbs of the cheekpieces 

 stand nearl}' perpendicular to the general line of the 

 horse's nose. This, of course, brings its lower limbs 

 in the opposite direction toward the neck, and the rod 

 ^ i^ is then gently shoved up till it presses lightly into 

 the chin-groove, taking care that the gauge stands 

 square, and that the mouthpiece lies equably on both 

 bars of the mouth. The rod g h is then screwed fast, 

 while the screw of the cheekpiece e J"\s loosened alto- 

 gether, so that the latter may be removed without 

 disturbing the rod g h; we then read off the height of 

 the bar on the lower limb of ef^ and have all the neces- 

 sary dimensions. 



It would be quite possible to take another measure- 

 ment — namely, that of the thickness of the tongue, by 

 placing the bar a b over that organ ; but it has been 

 alreadj^ shown that it is its relative and not absolute 



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