EYE. 383 



lower lid, and flow along to the inner corner of the eye. There 

 they are received through very small apertures into the lach- 

 rymal canals, and then they pass through the nasal duct (Fig. 

 LXVII. d, d) into the nose. 



FIG. LXVII. Lachrymal Apparatus. 



a, Lachrymal gland. 



b, Lachrymal ducts. 



c, c, Lachrymal canals. 



d, d, Nasal duct. 



892. The lachrymal canals are sometimes inflamed and 

 closed, and the passage for the tears into the nose is thus 

 stopped. The tears then find no outlet, and flow over upon 

 the cheek, causing some irritation. 



893. This apparatus sympathizes with the moral affections. 

 The tears are prepared in the gland, and flow more abun- 

 dantly than they can be received in the canals, in grief, and 

 sometimes in joy, and then they flow over the cheeks. 



894. The eye is rolled by a set of muscles peculiar to itself. 

 These are attached by one end to the bony socket, and by the 

 other to the eyeball. By their contractions they roll the eye 

 in every direction ; and, by their cooperation, both eyes are 

 directed to a single object. 



895. In cross-eyed persons, these muscles do not work in 

 harmony ; some one acts more powerfully than the correspond- 

 ing muscles, and draws one eye to one side more than the 

 other : this is most commonly inward. 



