Page:Handbook for Boys.djvu/249

228 they are only the result of something else. Of course there are exceptions. Sometimes wild hairs and skin disease affect the eyes. Eye strain should be removed by wearing well-fitting glasses and then these other conditions will disappear. If constent headache is experienced or the eyes itch or become tired easily, there is possibly eye strain.

One way to test the eye is for vision. Place the following letters fifteen feet from you. If you cannot read them clearly with both eyes and with .each eye separately, consult a first-class oculist.

Never buy eye-glasses unless fitted by an expert. Such glasses should be worn in proper relation to the eyes. They should not be permitted to slide forward on the nose or tilt. They may need to be changed often as the eyes grow better.'

For reading, a good, steady light is needed. Never sit in front of a window facing it to read. Always have the light come from the rear and over the left shoulder preferably. The book should be held on a level with the face and not too close. Sit