ON CHLOROFOKMING HOESES. 217 



For instance, when man found that his unshod horse 

 conld only carry him per day a small number of miles, he 

 invented for and presented him with iron shoes, in return 

 for wliich he required the wearer thereof to carry him 

 more than double that distance. 



To the old fashioned lever, attached to the extremity 

 of which a horse revolving a mill could only draw up per 

 day a small quantity of water, or knead a small quan- 

 tity of clay, man as he improved in mechanical know- 

 ledge added a wheel, in return for which he required the 

 quadruped worker thereof to lift treble the amount of 

 water, or to knead treble the amount of clay. 



Along the rough muddy roads that existed throughout 

 Europe half a century ago, a horse could with difficulty 

 draw a single man seated in his gig or "buggy." As 

 soon, however, as by human science roads were mac- 

 adamised, i.e., levelled and improved, there arose as it 

 were out of them (like mushrooms in a meadow) innu- 

 merable descriptions of four-wheeled carriages, in which 

 the horse, simply because he was enabled, was required 

 to draw, in addition to his master, his wife and three 

 or four of their children. 



When by the invention of railways the locomotive en- 

 gine suddenly superseded animal power, the horses, 

 instead of sharing in a discovery by human reason 

 which seemed to promise to them emancipation from 



