THE BONES. 41 



the middle of the foot. Three wedge-shaped and one cuboid botfe 

 in front of these complete the tarsus, and support the bones of the 

 instep. The five bones of the metatarsus are each about two inches 

 and a half long ; they are attached posteriorly to the solid part of 

 the foot, and anteriorly they support the toes. Their anterior ends 

 rest upon the ground in standing ; so that the foot presents an arch, 

 the end of the heel bone behind, and the ends of the metatarsal 

 bones in front, being the abutments, while the pulley-like bone is 

 the keystone on which the weight of the body rests. This arch is 

 not, however, firm or rigid, but yields a little when leant on ; and to 

 prevent its yielding too much, is strengthened below with strong 

 ligaments, passing like a bowstring from behind forwards. The 

 degree of hollowness is very different in different persons ; and 

 those in whom it is most developed are always most active, and 

 the best pedestrians. The foot is also arched from side to side ; 

 and in the hollow thus gained, the blood-vessels, nerves, and ten- 

 dons going to the toes, lie secure from injury by pressure. The 

 metatarsal bone of the great toe is much stronger than that of any 

 of the rest. To this toe there are only two movable pieces, much 

 larger than those of the other toes. Each of the smaller toes has 

 three pieces, similar to the pieces of the fingers, but much smaller, 

 as they are not intended for laying hold with. The last piece is 

 enlarged at the point, for supporting the nail on its upper, and the 

 pulpy extremity of the toe on its lower surface. 



The upper extremities have a strong general resemblance to the 

 lower, the shoulder corresponding to the pelvis, the arm to the 

 thigh, the forearm to the leg, and the hand to the foot ; but the 

 differences between them are also very striking. The lower limbs 

 are formed for progression, and for supporting the weight of the 

 rest of the body ; the upper are formed for prehension, much less 

 strong, but much more movable. The shoulder is not fixed im- 

 movably to the trunk ; the shoulder-blade, formed by the clavicle 

 and scapula, glides on the back of the ribs, and is joined firmly to 

 the outer end of the collar-bone ; and the inner end of this is con- 

 nected to a socket on the upper corner of the breast-bone, which 

 permits great freedom of motion, but forms a centre, round which 

 the shoulder plays, being capable of being raised or depressed, 

 carried forwards or backwards. The collar-bone is slender, curved 

 like a long italic f ; and as all shocks produced by falls on any 

 part of the upper extremity are transmitted through it, it is one of 

 the bones the most frequently broken. The scapula or shoulder- 



