216 OS CUNEIFORMS. 



Os cuneiforme, or minimum, is still more exactly the shape 

 of a wedge than the former. Its upper part is square ; its in- 

 ternal side has a flat smooth surface for its connexion with the 

 adjoining bone; the external side is smooth and a little hol- 

 lowed, where it is contiguous to the last described bone. Be- 

 hind, this bone is triangular, where it is articulated with the os 

 naviculare ; and it is also triangular at its forepart, where it is 

 contiguous to the os metatarsi of the toe next to the great one. 



The broad thick part of the os cuneiforme maximum, or in- 

 ternum, is placed below, and the small thinner edge is above. 

 The surface of the os cuneiforme behind, where it is joined to 

 the os naviculare, is hollow, smooth, and of a circular figure 

 below, but pointed above. The external side consists of two 

 smooth and flat surfaces. With the posterior, that runs ob- 

 liquely forwards and outwards, the os cuneiforme minimum is 

 joined ; and with the anterior, whose direction is longitudinal, 

 the os metatarsi of the toe next to the great one is connected. 

 The forepart of this bone is flat and smooth, for sustaining the 

 os metatarsi of the great toe. The internal side is scabrous, 

 with two remarkable tubercles below, from which the muscu- 

 lus abductor pollicis rises, and the tibialis anticus is inserted 

 into its upper part. 



The three cuneiforme bones are all so secured by ligaments, 

 that very little motion is allowed in any of them. 



These seven bones of the tarsus, when joined, are convex 

 above, and leave a concavity below, for lodging safely the 

 several muscles, tendons, vessels, and nerves, that lie in the 

 sole of the foot. In the recent subject, their upper and lower 

 surfaces are covered with strong ligaments, which adhere firmly 

 to* them ; and all the bones are so tightly connected by these 

 and the other ligaments, which are fixed to the rough ridges 

 and fossae, that notwithstanding the many surfaces covered 

 with cartilage, some of which are of the form of the very 

 movable articulations, no more motion is here allowed, than 

 is necessary to prevent too great a shock of the fabric of the 

 body in walking, leaping, &c., by falling on too solid a base. 

 If the tarsus was one continued bone, it would likewise be 



