INTRODUCTION. V 



termed the crusta petrosa. The body of such a tooth 

 is long wearing down ; and when it does wear away, 

 the bony matter inside, and the crusta petrosa out- 

 side, yield first, and the enamel is left projecting; so 

 that they will always present unequal surfaces. To 

 this must be added that they are formed with long 

 fangs and are pushed upwards into the mouth after 

 they are fully cut ; and the grinding surfaces of these 

 teeth consequently will stand at nearly the same 

 height so long as the horse may live. 



Wolves' Teeth. — There is often found before the 

 grinder an additional tooth, which is always of small 

 size: strange stories are told of the injury these 

 trivialities sometimes occasion. There is no proof of 

 the mischief which they accomplish, They have been 

 seen in the mouths of horses sixteen years old, that 

 have never appeared to suffer the least inconvenience. 

 Should it ever seem desirable to remove them, this 

 may be easily effected with the common keyed instru- 

 ment used for extracting human teeth, or even with a 

 pair of small pincers, for they are not firmly rooted in 

 the jaws. 



The Lower Jaw. — Some attention should be paid 

 to the size of what is called the channel, that is, to the 

 space between the branches of the lower jaw. If it is 

 narrow, the head will sit awkwardly ; for the rounded 

 termination of the windpipe cannot be readily re- 

 ceived between the approximated branches ; the head 

 will then always be poking out, diminishing mate- 

 rially the beauty of the horse, and being a sad incon- 

 venience to the rider. There are few things of so 

 much importance to the pleasure of the rider or driver, 

 b5 



