92 PHYSIOLOGY. 



the knee, is a movable bone of a flat, round shape, called pa- 

 tella, or knee-pan, over which a cord or tendon passes, which 

 is made by a contraction of all the muscles on the fore part 

 of the thigh. This serves as a pulley, and enables the mus- 

 cles to act to greater advantage, by increasing the distance 

 of the rope from the centre of motion. 



53. \ The leg below the knee, is composed of two bones, 

 tibia and fibula, of a three-cornered or angular shape, 

 like those of the fore-arm ; and the design no doubt is, to 

 form a pillar of greater strength than one bone would 

 make ; and also to furnish a greater surface for the origin 

 and attachment of the numerous muscles required for the 

 feet. ;f The ankle, like the wrist, the elbow, and the knee, is 

 a perfect hinge of great strength. In front of it there is a 

 narrow strap, or ligament, which binds down the cords 

 which go to move the toes. There is a small groove just 

 within the inner ankle, for the passage of a tendon, exactly 

 like a little pulley) The heel is a lever for those strong mus- 

 cles to act by, which form the calf of the leg. It is the ac- 

 tion of these muscles, pulling on the heel, that lifts the body, 

 in walking, dancing, standing on the toes, dec. In the negro, 

 the heel is longer than in any other race of mankind. 



54. The bones of the foot are divided into the tarsus, 

 which is composed of seven bones, reaching from the heel 

 to the middle of the foot.) The metatarsus consists of five 

 long bones, parallel to each other, which extend from the 

 tarsus to the roots of the toes. The bones of the toes are 

 called phalanges, from being in the form of a phalanx. 

 There are in all thirty-six bones in the foot, and as each 

 bone forms a joint, and as each joint not only permits 

 motion, but bestows elasticity, the obvious design of this 

 number is to render the foot elastic, and thus save the body 

 from shocks... It should be recollected that each bone is 

 tipped with cartilage, that the fibres composing cartilage 

 are disposed longitudinally or perpendicularly to the surface 

 of the bone and the pressure made upon it ; thus acting like 



