THE EFFECT OF CONDITION AND PRACTICE. 65 



might suppose that youth would better endure 

 such harass than age. Such, however, was not 

 usually found to be the case : thus it will be seen 

 that in mankind, youth and more advanced age 

 can equally bear considerable fatigue, but both 

 can best bear it in a different way ; and I have 

 found it the same with horses. 



We have now steeple-chase horses going at 

 from ten to fifteen years old. I am quite clear 

 that in nine cases in ten with these, if we were 

 to throw them up for twelve months, they Avould 

 never come out again in as good form as they 

 are, however great screws and cripples some may 

 be. 



We know quite well that extreme exertion in 

 youth is apt to come against us in age. I quite 

 grant such to be a fact to be anticipated; but 

 then the question may arise, " At w^hat age is 

 such eff'ect likely to manifest itself ? '^ This re- 

 quires some little explanation. Of course the 

 amount of eflPect, and the age at which it will 

 probably be felt, depends on circumstances and 

 also on persons. 



All persons more or less possess considerable 

 elasticity of limbs at twenty years of age ; how 

 long this may last depends, in most cases, on how 

 far the situation, circumstances, constitution, and 

 inclination of the person permit, or induce him 

 to take the exercise and practice necessary to 



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