CHAPTER I. 



INTRODUCTORY. 



CIRCULATING SLIDES THE LITTLE SPECIAL AP- 

 PARATUS NEEDED USE OF EYEPIECES 

 FIRST ATTEMPTS. 



Although the sense of sight enables us to see 

 the many forms around us, there is a world as 

 absolutely invisible to the unassisted eye as the 

 familiar objects of life are invisible to the blind. 

 To those who have eyesight, however, the micro- 

 scope bestows as great a power of vision as the 

 gift of sight would bestow upon the blind, for it 

 enables them to penetrate the secrets of nature's 

 realm, which without such assistance would for 

 ever remain a mystery. 



A very small magnification will often reveal de- 

 tails of construction sufficient to call forth exclama- 

 tions of surprise ; and, indeed, with microscopists 

 it is a matter of common knowledge that whole 

 insects or parts of plants viewed under a low power 

 will excite more astonishment than the resolution 

 of a difficult diatom under the very highest power. 

 For instance, a spider magnified ten times seems 



