i«B. 77 



of all vouno: horses, about four or five years of age. 

 immediately above the hifurcation, is invariably tliick 

 and very round at the bottom ; the cavity of saia bone 

 being very small, contains a good deal of marrow, and 

 generally continues in this state until the animal arrives 

 at that period which is generally termed an "aged 

 horse," or until the animal acquires his full size in 

 height or thickness ; or according t(, "porting language^ 

 is completely furnished, with very httle variation. But 

 after this period, the cavity as aforesaid becomes larger, 

 and more marrow is contained therein. Hence the 

 submaxillary bone becomes thinner and sharper a little 

 above the bifurcation. 



This indelible mark may always be observed in a 

 small degree in horses above eight years of age ; but at 

 nine years old it is still more perceptible. It continues 

 growing a little thinner and sharper at the bottom until 

 twelve years of age. From thence until fifteen, it is 

 still thinner, and about as sharp as the back of a case 

 knife near the handle. From this period until the 

 ages 18, 19, 20, and upwards, it is exceedingly so ; 

 and is as sharp, in many subjects, as the dull edge of 

 that instrument. 



RULES. 



1st. Put your three fingers about half an inch or an 

 inch immediately above the bifurcation, and grasp the 

 submaxillary bone, or the lower jaw bone. If it is thick 

 at the sides, and very round indeed at the bottom, the 

 animal is most certainly under nine years of age. 



2d. If the bone is not very thick, and it is per 

 ceivably not very round at the bottom, he is from nme 

 to twelve years old, and so on. From twelve to fifteen, 

 the bone is sharper at bottom, and thinner at ine 



