320 NATURAL THEOLOGY. 



mucus on the surface of the third eyelid. It flows 

 very copiously ; and this is probably the reason of 

 the smallness of the proper lachrymal gland which 

 lies on the opposite side of the orbit. 



We already see two objects attained through the 

 motion of these parts : the moistening of the eye 

 with the clear fluid of the lachrymal gland, and the 

 extraction or protrusion of oflTensive particles. 



There is another part of this subject no less cu- 

 rious : the diflferent conditions of the eye during 

 the waking and sleeping state. If we approach a 

 person in disturbed sleep when the eyelids are a 

 little apart, we shall not see the pupil or the dark 

 part of the eye, as we should were he aw^ake, for 

 the cornea is turned upwards under the upper eye- 

 lid. If a person be fainting, as insensibility comes 

 over him the eyes cease to have speculation ; they 

 want direction, and are vacant, and presently the 

 white part of the eye is disclosed by the revolving 

 of the eyeball upwards. Look to a blind beggar ; 

 those white balls are not turned up in the fervour 

 of entreaty ; it is the natural state of the eyeballs, 

 which are totally blind, and from the exercise of 

 which the individual has withdrawn his attention. 

 So it is on the approach of death ; for, although 

 the eyelids be open, the pupils are in part hid, 

 being turned up with a seeming agony, which, 

 however, is the mark of increasing insensibility. 

 These motions of the eye for the protection of the 

 organ do not interfere with vision ; they are per- 

 forjned unconsciously, and so rapidly that the im- 



