THE MINUTE. 



tiny form while the background is dark behind 

 it! 



It is a startling thought that there exists a 

 world of animated beings densely peopling the 

 elements around us, of which our senses are alto- 

 gether uncognisant. For six thousand years gen- 

 eration after generation of Rotifern and Ento- 

 inostnic;!, of lufusorhi and Protozoa have been 

 living and dying, under the very eyes and in the 

 very hands of man; and, until this last century or 

 so, he has no more suspected their existence than 

 if " the scene of their sorrow'' had been the ring 

 of Saturn. Dr. Mantell wrote a pretty book, the 

 secondary title of which was "A Glimpse of the 

 Invisible World." It was a book about the Ani- 

 malcules, which are revealed only by the micro- 

 scope ; and though it gave little original informa- 

 tion, and some of that unsound, yet, for the time, 

 when the microscope was in far fewer hands than 

 it is now, it contained much to interest and much 

 to instruct. The minutely invisible world has 

 now become tolerably familiar to most persons of 

 education; and thousands of eyes are almost con- 

 stantly gazing on the surprising forms of animals 

 and plants, which the microscope reveals. 



The study of one particular class of these or- 

 ganisms, the Diatoms, has become quite a fashion, 

 and the reunions of our microscopists are almost 

 exclusively occupied Avith the names, the scientific 

 arrangement, the forms and sculpturings of these 

 singular objects. 1 have already had occasion to 

 mention them in relation to the important part 

 they play in the economy of creation ; but it may 

 not be amiss to devote a few words more to 

 them, with the view to make the reader better 

 acquainted with their general appearance. 



A flat pill-box or cylindrical tin canister, which 

 1-49 



