PEEFACE. 



THE object of this little work is to furnish an 

 elementary course of instruction in the use of 

 the Microscope, and on its application to the ex- 

 amination of the structure of plants and animals. 

 Assuming that the reader has had no previous 

 acquaintance with the Microscope, or with the 

 study of natural history, I have attempted to render 

 the descriptions of the objects as simple as possible. 

 At the same time, the technical terms have been 

 added and explained, in order gradually to render 

 them familiar to the reader, and thus facilitate 

 the future study of larger and more detailed works. 

 The objects figured and described comprise the prin- 

 cipal structures and more minute forms of both 

 the vegetable and the animal kingdom, those having 

 been selected which are common and readily pro- 

 curable. 



A chapter has been given upon the optical priri- 



