2 ELEMENTS OF APPLIED MICROSCOPY. 



as corresponding to a definite object perceived by the 

 other senses. The image is in all cases inverted, but in 

 infancy it is found that images upside down correspond 

 to objects which are really right side up. Experience 



Fig. I. — Section through the Human Eye, 

 (After Everett-Deschanel.) 



K. Retina. 

 L. Vitreous humor. 

 M. Optic nerve. 

 N. Inferior rectus muscle. 

 O. Superior " " 



P. Levator palpebrse muscle. 



A. Cornea. 



B. Aqueous humor. 



C. Pupil. 



D. Iris. 



E. Lens. 



F. Suspensory ligament. 



G. Accommodation muscle. 

 H. Sclerotic coat. 

 /. Choroid coat- 



%■ r Meibomian glands. 



teaches, also, that an image of a certain size produced 

 by an object at a given distance always implies a 

 definite magnitude; and we are therefore able to judge 

 something about the actual size of an object from the 

 size of its image and our knowledge of its remoteness. 



