ON THE HACKNEY AND HUNTER. I77 



rendered reftiff, or vicious, from infufficient 

 breaking, or acquired habits. The firft is ever 

 a loft cafe, whatever the moft fkilful domitor 

 equorum may pretend to the contrary ; and in 

 the fecond, the cure is but uncertain at beft, 

 which will be allowed, by all thofe, who have 

 confidered the mighty power of habit, even 

 among us two-legged animals, who vaunt fo 

 highly of the ftrength of our reafoning facul- 

 ties. The difciples of Locke will deny the ex- 

 iftence of innate qualities, fuch as I have fup- 

 pofed. They fhould, I think, furnifli fome new 

 hypothefis, on which to account for the fol- 

 lowing facls, the truth of which will be allowed, 

 by all who have had much experience in Horfes. 

 Two colts, of like age, fhall be broke at the 

 fame time, by perfons of equal (kill, or by the 

 fame perfon. They (hall be treated precifely 

 in the fame manner, in all refpe&s ; and yet the 

 one fhall be tamed to obedience, with only the 

 common difficulties, and remain perfectly quiet; 

 whilft the other, even if rendered fomewhat 

 tame at firft, (hall always obey with reluctance, 

 and continue felf-willed and reftiff all his life. 

 Reftivenefs, and various other qualities, bad or 

 good, are alfo known to be fometimes heredi- 

 tary, and to run through many generations. 

 Do not thefe natural tendencies, (granting their 

 exiftence) either in man, or beaft, arife from 

 the accidental variation of fpecific quantity in 

 vol. 1. n the 



