The, Foot. 361 



margin which is immediately in contact with the wall 

 assisting. When we remember that the sole is concave, it 

 will be clear that it has some other function than that of 

 weight-bearing to perform : its function is to protect the 

 sensitive sole and pedal bone. 



The folding up of the horny and sensitive leaves in the 

 foot, in the manner above described, has another function 

 besides that of merely supporting the weight and rendering 

 the union firm. 



It is clear that by folding up this amount of material 

 the surface of the foot is considerably increased. In 

 other words, by this arrangement the foot has been kept 

 within small proportions, without affecting its stability. 

 A book, say of 500 pages, may, by placing one leaf on the 

 other, be made to occupy a bulk represented by a few 

 inches; but if each page be laid out separately on the 

 ground, and made to touch one another, the surface covered 

 will be considerable. This is exactly what occurs in the 

 foot. The horny and sensitive leaves by their singular 

 arrangement increase the surface of the foot, and yet keep 

 it within reasonable bounds. Bracy Clarke, who first had 

 a calculation made as to the increased surface afforded by 

 this arrangement, came to the conclusion that it was equal 

 to H square feet ; but Moeller* has estimated that it is 

 equivalent to 8 square feet ; whilst Gader's estimatef is 

 lOf square feet. For safety we will adopt Moeller's 

 number. 



The bearing surface afforded by each foot is equivalent to 

 8 square feet, affording a total area for the pedestals of 

 32 square feet. 



The physiological function of the leaves of the foot is 

 demonstrated by pathological observation. Inflammation 

 of the leaves occurs either through over-work, or through 

 an animal standing too long in one position ; in either case 

 they get strained, and resent it. We all know the practical 

 value of exercising horses which from any reason have to 



* Veterinary Journal, vol. v. 



+ Quoted by Goubaux and Barriere. 



