4 HOW TO USE THE MICROSCOPE 



natural history. The rock-pool on the seashore 

 yields abundance of Uving creatures which may be 

 studied with the naked eye, but it also contains 

 objects of the most interesting nature and habits 

 which the pocket lens enables us to observe. It 

 extends the field of observation in every direction. 

 Some flowers are so small that their parts can be 

 barely distinguished without the aid of the lens, 

 and it is indispensable to the botanist who means 

 business. The entomologist uses it in the examina- 

 tion of insect parts and in other respects ; he also 

 finds it mdispensable. The geologist needs it in 



Fig, 1. — Simple Pocket Magnifier. 



his study of soils, rocks, minerals, and fossils ; the 

 general zoologist must never be without it. 



The lens has an sesthetic as well as a scientific 

 value ; it stimulates our sense of the wonderful and 

 beautiful ; it ministers to poetry. He must uideed 

 be dull of soul who is not stirred by the exquisite 

 coloration and symmetry of an insignificant flower 

 as it appears in a magnified image. 



Pocket lenses are purchasable in several forms. 

 Cheap single glasses may be had in metal, ebonite, 

 vulcanite, or tortoiseshell mounts. For two or 

 three shillings a mount can be obtained, including 

 three lenses, which may be used separately or in 

 combination. The ordinary watchmaker's glass is 



