The Sense of Sight. 261 



10. Irritation of the Eyes. If one finds himself rubbing 

 his eyes, it is a sign that they are irritated. Stop read- 

 ing, find the cause, and do not read on unless the irritation 

 ceases. If any foreign object, as a cinder, lodges in the 

 eye, it is better not to rub the eye, but to draw the lid 

 away from the eyeball and wink repeatedly ; the increased 

 flow of tears may dissolve and wash the matter out. If it 

 be a sharp-cornered cinder, rubbing may merely serve to 

 fix it more firmly in the conjunctiva. If it does not soon 

 come out, the lid may be rolled up over a pencil, taking 

 hold of the lashes or the edge of the lid. The point of a 

 blunt lead pencil is a convenient and safe instrument with 

 which to remove the particle. 



1 1. Keep the Eyes Clean. Be careful to keep the eyes 

 clean. Do not rub the eyes with the fingers. Aside from 

 consideration of rules of etiquette, there is danger of intro- 

 ducing foreign matter that may be very harmful. It is 

 very desirable that each person have his individual face 

 towel. By not observing this rule certain contagious 

 diseases of the eyes often spread rapidly. 



12. Consult a Reliable Oculist. If there is any con- 

 tinuous trouble with the eyes, consult a reliable oculist. 

 Many headaches are due to eye-strain, the real cause being 

 unsuspected. If a child has frequent headaches, it is well 

 to have the eyes examined. Many persons injure their 

 eyes by not wearing suitable glasses. On the other hand, 

 do not buy glasses of peddlers nor of any but reliable 

 specialists. One may ruin the eyes by wearing glasses 

 when they are not needed. Sight is priceless. 



Summary. i. The eye is protected by its bony surroundings, lids, 

 lashes, tears, sensitiveness of the conjunctiva, etc. 



2. The eye has three coats sclerotic, choroid, and retina. 



