EVIDENCE OF AGE AFTER TEN YEARS 401 



EVIDENCE OF AGE AFTER TEN YEARS 



Some years ago Mr. Sidney Galvayne made public a new method of 

 judging the age of the horse up to the latest period of the animal's life, 

 and as his system has proved to be extremely useful when it has been 

 applied to old horses, the date of whose birth happened to be known or 

 could be ascertained within reasonable limits by collateral evidence, it is 

 desirable to rely upon that system exclusively after the age of ten years. 



Mr. Galvayne's discovery, as it may be called, is based on the existence 

 of a groove in the fang of the upper corner incisors. The groove is not 

 visible in the living animal until the age of ten years, by which time 



Fig. 618. (a) Groove at the side of Upper Corner Fig. 619. (ft) Groove reaching half-way down the 



Incisor at ten years Corner Incisor at fifteen to sixteen years 



the bone of the alveolar cavity, which contains the tooth, has shrunk. The 

 tooth meanwhile has grown, or has been pushed forward, to an extent 

 corresponding with the wear at the surface, and the lateral groove is 

 exposed as shown in the next figure (fig. 618). 



The method of judging the age from the point indicated in the above 

 illustration is extremely simple. It is only necessary to recollect that, as 

 the tooth continues to grow, and is at the same time constantly being 

 worn, that part of the groove which is shown in fig. 618 will, at a certain 

 period, be at the bottom of the tooth, and therefore year after year more of 

 it will be seen. Eleven years, according to Mr. Galvayne's calculation, will 

 elapse before the bottom of the groove reaches the cutting edge of the 

 tooth. At that time, consequently, the animal will be twenty-one years 

 old. When it is half-way down the tooth, as shown in fig. 619, the horse 

 will be about sixteen years old. 



The appreciation of the exact value to be attached to the gradual 

 advance of the groove year by year can only be the result of close observa- 

 tion, but in any case the method is more reliable than any other which has 



