78 NATURAL THEOLOG-Y 



rather, it makes a part of their continuation — from their ori- 

 nrin in the thigh to their insertion in the tibia. It protects 

 both the tendon and the joint from any injury which either 

 might suffer by the rubbing of one against the other, or by 

 the pressure of unequal surfaces. It also gives to the ten- 

 dons a very considerable mechanical advantage, by altering 

 the line of their direction, and by advancing it further out 

 from the centre of motion ; and this upon the principles of 

 the resolution of force, upon vi^hich principles all machinery 

 is founded. These are its uses. But what is most observ- 

 able in it is, that it appears to be supplemental, as it were, 

 to the frame ; added, as it should almost seem, afterward ; 

 not quite necessary, but very convenient. It is separate 

 from the other bones ; that is, it is not connected with any 

 other bones by the common mode of union. It is soft, or 

 hardly formed, m infancy ; and produced by an ossification 

 of the inception or progress of which no account can be given 

 from the structure or exercise of the part. 



VI. The shoulder -blade is, in some material respects, a 

 very singular bone, appearing to be made so expressly for 

 its own purpose, and so independently of every other reason. 

 In such quadrupeds as have no collar-bvones, which are by 

 far the greater number, the shoulder-blade has no bony com- 

 munication with the trunk, either by a joint, or procc^., or 

 in any other way. It does not grow" to, or out of, any 

 other bone of the trunk. It does not apply to any other 

 bone of the trunk — I know not whether this be true of any 

 second bone in the body, except perhaps the os hyoides — in 

 strictness, it forms no part of the skeleton. It is bedded in 

 the flesh, attached only to the muscles It is no other Ihati 

 a foundation bone for the arm, laid in separate as it were, and 

 distinct from the general ossification. The lower limbs con* 

 uect themselves at tho hip with bones v/hich form pa it of 

 the skeleton ; but this connection in the upper limbs being 

 wanting, a basis, whereupon the arm might be articulated, 

 was to be supplied by a detached ossification for the purpose 



