ORGANS OF SPECIAL SENSE THE EYE 361 



Flickering Light. A light whose intensity is constantly 

 changing is very tiresome. It is injurious to read by candle- 

 light, not so much because it is dim, as because it is not 

 steady. Reading in the cars is very taxing because the im- 

 ages on the retina are those of an object which is constantly 

 shaken by the motion of the car. 



Resting the Eyes. Eyes are made for use and if properly 

 treated will grow stronger, but if overtaxed they will 

 suffer quickly. Reading fine print or looking intently and 

 constantly at small objects is always severe on the eyes. 

 Everyone whose work requires such application should 

 appreciate the need of giving the eyes an occasional rest by 

 looking off at distant objects, or by ceasing to use them at all. 

 If rested in this way ihey may be used for exacting work for 

 years without injury. 



Injuries. The eyes are too delicate to be carelessly treated 

 and injuries to them usually need the attention of a physician. 

 A particle of dust or a cinder in one's eye can usually be re- 

 moved with ease, however. In most cases tears will quickly 

 wash it over the surface to the tear duct. This process may 

 be assisted by seizing the lids with the fingers and lifting them 

 away from the eyeball, when the tears that accumulate will 

 ordinarily dispose of the dust. The eye should not be rubbed. 

 If the dust particle is under the lower lid, this can easily be 

 lifted and the particles be removed on the corner of a hand- 

 kerchief; if it is under the upper lid, this can be rolled up 

 gently over a lead pencil. A physician should, however, take 

 care of any serious eye trouble. 



