242 



DETAILED SYNTHESIS. 



FIG. 177. 



eral fasciculi, neither of which contracts in the line of 

 motion ; others by the successive action of fasciculi, and 

 others again in a direction opposite to the direction of 

 fascicular action, produced by a changed direction of the 

 tendon. (See 9, in succeeding figure.) 



Fig. 177 represents a 

 section of the socket of 

 the eye and that organ 

 with its muscles in situ. 

 4, the muscle that ele- 

 vates the lid, a part of 

 which, with the lashes, 

 has been cut off and left 

 with the muscle ; 10, 

 points to the loop of lig- 

 ament round which 11, 

 the tendon of the mus- 

 cle, 9, turns, a bursa be- 

 ing interplaced to pre- 

 vent friction. A farther 

 description of the mus- 

 cles of the eye will be 

 given when that organ 

 is described. 



477. Sometimes ALL THE FASCICULI OP SEVERAL 

 MUSCLES will be required to produce a desired motion, 

 and again all those of one and only a few of another. 



478. Thus by THE VARIED DIRECTION OF THE FASCI- 

 CULI, and by combining the action of muscles or parts 

 of muscles, all kinds of desired motion can be produced. 



479. THE EXTENT OF MOTION DEPENDS UPON the 

 length of the fasciculi, and the strength of motion upon 

 the number of them. 



480. MOST OF THE MUSCLES ARE ATTACHED to the 



skeleton so as to produce rapid motions at the expendi- 

 ture of strength, for they are usually attached near the 

 joint. As a hand near the hinge of a gate must use 

 great exertion to swing it, so must the muscle to move 

 the part to which it is attached. 



Describe Fig. 177. 477. What said of ? 478. What said of ? 419. what ? 

 480. How - ? 



