348 APPLIED PHYSIOLOGY 



objects; and by a light in front of the unshaded 

 eyes. 



8. Show that the iris protects the retina against too 



strong light. 



9. Show that the lens must change its shape to accom- 



modate itself to near vision and to far vision. 



10. Tell the condition of the lens and the remedy in far 



sight ; in near sight ; and in astigmatism. 



11. Describe a cataract and its remedy. 



12. Show how two eyes aid in the judgment of form and 



position. 



13. Describe the condition of the eye muscles in a cross- 



eyed person, and tell how vision is affected. 



14. Show how reading upon a moving railway train and 



reading while lying down overwork the eye mus- 

 cles. 



15. Tell how to care for an eye which runs matter, and 



how to remove a speck of dirt from under the lid. 



1 6. Show that rubbing a sore eye is always liable to do 



harm. 



17. Show that irritation of the eye may produce false 



sensations of sight; and that sight memories may 

 seem to be real again. 



1 8. Describe the X rays. 



19. Describe the effects of alcohol and tobacco on the 



eye. 



20. Describe the eye in lower animals ; in insects ; and in 



a leech. 



