186 THE IMPROVED ART OF FARRIERY. 



11. The external frog is convex, and although 

 horny and insensible, is softer and more elastic than 

 the sole ; their nature is totally distinct, yet they are 

 firmly united. 



12. The sensible frog corresponds with the horny 

 in form, is very elastic, and united by cartilages. 



13. The use of the frog is to give safety to the pace 

 of the animal, and prevent it from slipping : the sen- 

 sible and horny frogs, by their great elasticity, act as a 

 spring, and at the same time are powerful agents in 

 expanding the heels : when the frog is too much ele- 

 vated above the ground, and its substance cut or worn 

 away, contraction of the foot must follow. Some 

 writers, among whom is Mr. St. Bel, assert that the 

 frogs are to protect the tendon ; this notion is now 

 exploded. 



14. The foot is filled with nervous fibres, ligaments, 

 cartilages, blood-vessels, &c., and consequently highly 

 sensible and elastic. 



The hoof of a colt feels no inconvenience from the 

 hardest roads ; the necessity of employing a shoe, how- 

 ever, is unavoidable, since by friction the hoof is ra- 

 pidly worn away. Shoes are not required to be broad 

 in the surface, indeed the narrower they are the better 

 and firmer hold the foot will have, especially on turf or 

 soft slippery ground. 



The greatest evil in shoeing arises from the intro- 

 duction of nails ; and notwithstanding many men 

 of note in the veterinary art have strenuously laboured 

 to obviate the mischief, or to discover some new and 

 better mode of fixing the shoe, their efiforts have not 

 hitherto been crowned with success. 



Great ignorance was displayed in the earlier methods 

 of shoeing: the bars were totally cut away, and the 

 frog considerably pared down ; the shoe was badly 



