THE PROCESS OF TEETHING. 201 



Horsemen, after the animal is eight years old, are accustomed to look to the 

 nippers in the upper jaw, and some conclusion lias been drawn from the 

 appearances which they present. It cannot be doubted that the mark remains 

 in them some years after it has been obliterated from the nippers in the lower 

 jaw; because the hard substance, or kind of cement, by which the pit or funnel in 

 the centre of the tooth is occupied, does not reach so high, and there is a greater 

 depth of tooth to be worn away in order to come at it. To this it may be added 

 that the upper nippers are not so much exposed to friction and wear as the 

 under. The lower jaw alone is moved, and pressed forcibly upon the food : the 

 upper jaw is without motion, and has only to resist that pressure. 



There are various opinions as to the intervals between the disappearance of 

 the marks from the different cutting-teeth in the upper jaw. Some have 

 averaged it. at two years, and others at one. The author is inclined to adopt the 

 latter opinion, and then the age' will be thus determined : at nine years the 

 mark will be worn out from the middle nippers — from the next pair at ten, and 

 from all the upper nippers at eleven. During these periods the tush is like- 

 wise undergoing a manifest change — it is blunter, shorter, and rounder. In 

 what degree this takes place in the different periods, long and most favourable 

 opportunities for observation can alone enable the horseman to decide. 



The tushes are exposed to but little wear and tear. The friction against 

 them must be slight, proceeding only from the passage of the food over them, 

 and from the motion of the tongue, or from the bit ; and their alteration of 

 form, although generally as we have described it, is frequently uncertain. The 

 tush will sometimes be blunt at eight ; at other times it will remain pointed at 

 eighteen. The upper tush, although the latest in appearing, is soonest worn 

 away. 



Are there any circumstances to guide our judgment after this? There are 

 those which will prepare us to guess at the age of the horse, or to approach 

 within a few years of it, until he becomes very old ; but there are none which 

 will enable us accurately to determine the question, and the indications of 

 age must now be taken from the shape of the upper surface of the nippers. 

 At eight, they are all oval, the length of the oval running across from tooth 

 to tooth ; but as the horse gets older the teeth diminish in size, and this commen- 

 cing in their width, and not in their thickness. They become a little apart from 

 each other, and their surfaces are rounded. At nine, the centre nippers are 

 evidently so ; at ten, the others begin to have the oval shortened. At eleven, 

 the second pair of nippers are quite rounded ; and at thirteen the corner ones 

 have that appearance. At fourteen, the faces of the central nippers become 

 somewhat triangular. At seventeen, they are all so. At nineteen, the angles 

 begin to wear off, and the central teeth are again oval, but in a reversed direc- 

 tion, viz., from outward, inward ; and at twenty-one they all wear this form. 

 This is the opinion of some Continental veterinary surgeons, and Mr. Percivall 

 first presented them to us in an English dress. 



It would be folly to expect perfect accuracy at this advanced age of the 

 horse, when we are bound to confess that the rules which we have laid down 

 for determining this matter at an earlier period, although they are recognised 

 by horsemen generally and referred to in courts of justice, will not guide us in 

 every case. Stabled horses have the mark sooner worn out than those that are 

 at grass ; and a crib-biter may deceive the best judge by one or two years. 

 The age of the horse, likewise, being formerly calculated from the 1st of May 

 it was exceedingly difficult, or almost impossible, to determine whether the animal 

 was a late foal of one year or an early one of the next. At nine or ten, the bars 

 of the mouth become less prominent, and their regular diminution will designate 



