372 TYPES AND MARKET CLASSES OF LIVE STOCK 



usually levelled. At eleven years, the central enamel of the 

 upper corner teeth becomes elliptical and tends to disappear. 

 The lower teeth now show much wear, the central enamel forms 

 a small ring only, very close to the back border of the tooth, 

 while the dental star becomes narrower and also approaches 

 the back border. At twelve years, all of the lower teeth are 

 round, and sometimes the central enamel has disappeared, in 

 which case the wearing surfaces show only a small yellowish 

 spot which is the dental star. At fifteen years, the swallow 

 tail, which reappeared at ten years, is still in evidence, the teeth 

 tend strongly toward a triangular shape on the wearing surface, 

 and other indications of age become marked. At twenty-one 

 years, the swallow tail is gone again, and all indications of wear 

 are very marked. After ten or eleven years and on up to thirty 

 or more, only general indications serve as a guide to the age. 

 The horseman knows that the teeth change from oval to three- 

 sided with age, and that they project or slant forward more and 

 more each year. In very old horses these features are very 

 marked. 



In determining the age, a regular procedure should be fol- 

 lowed. First open the lips and determine whether the teeth 

 are temporary or permanent. Unless they are all permanent 

 it is usually unnecessary to open the mouth. If they are all 

 permanent, the wearing surfaces of the lower incisors should be 

 carefully examined first, and then the wearing surfaces of the 

 upper incisors. Also note the profile or slant of the teeth, and 

 the presence or absence of the hook or swallow tail on the upper 

 corner teeth. 



Mere description here will not enable the student to be- 

 come adept at determining age. Actual practice and the study 

 of many mouths are necessary in order to master this subject. 



Determination of the height of horses. The height of a 

 horse is determined by measuring the vertical distance from 

 the highest part of his withers to the ground. The unit in which 

 the height of horses is expressed is the hand. A hand is four 

 inches. A horse measuring 60 inches high is thus said to be 

 15 hands high; a horse measuring 63 inches is said to be "fifteen, 

 thr.ee/' meaning 15 hands, three inches, written 15-3; and one 

 measuring 65 inches is 16-1 hands high. The dividing line in 

 height between horses and ponies cannot be definitely fixed, 

 but is about 14 hands. Ponies vary in height from 14 hands 

 down to 8 hands or even less, while horses vary from 14 hands 



