288 THE TENDONS. 



being contained in a series of cells of the cellular tissue, all of 

 which are continuous with each other. The muscular matter is 

 found in general only in the middle part of the cellular tissue ; 

 the latter part is continued on at each extremity of the muscle, 

 where it is compacted into a solid mass, presents a ligamentous 

 appearance, and constitutes the tendons, or cords by which the 

 muscles are attached to the periosteum covering the bone. 

 Hence the tendons are continuous with, and must obey to a 

 certain extent the contraction of every muscular fibre. 

 The tendons exist under a great variety of forms : most 

 generally round or cylindrical, sometimes flat, radiated, bifur- 

 cated, etc., but are always susceptible, by a little dissection, of 

 being unfolded into a membrane. They have little vascularity, 

 no sensation in a healthy state, no nerves having ever been 

 traced into them, and are of a strength surpassing that of almost 

 any other substance of equal size. They have a great affinity 

 for phosphate of lime, especially in old persons, in whom it is 

 not very unusual to find them ossified ; and very frequently at 

 all stages of life, we find developed in their substance sesa- 

 moid bones. 



The muscles are often from inanition or want of use much 

 wasted away, the red muscular matter disappearing from the 

 cells in which its particles are contained. The cells however 

 remaining, if the system regains its vigor, or the muscles are 

 brought into use, they are filled anew with the muscular sub- 

 stance or myoline, and the muscle is restored to its former size, 

 and its contraction takes place again with its usual force. 

 - From this mode of formation, it is evident that there must be 

 an exact relation between the force of the muscle, and the 

 strength of its tendons, even when the muscle is most fully de- 

 veloped. The size and power of the muscle is much dependent 

 upon its use. 



w The muscles of the legs in dancers, of the arms in black- 

 smiths, of the shoulders and back in porters, all obtain an in- 

 crease of bulk from use, which still better fits them for the 

 duties they have to perform. This is strongly exemplified in 

 birds ; the breast bone and muscles attached to it being more 



