PREFACE. 



The rapid increase whicli has recently taken place in the use 

 of the Microscope, — ^both as an instrument of scientific research, 

 and as a means of gratifying a laudable curiosity and of obtain- 

 ing a healthful recreation, — has naturally led to a demand for 

 information, both as to the mode of employing the instrument 

 and its appurtenances, and as to the objects for whose minute 

 examination it is most appropriate. And as none of the existing 

 Treatises, either British or Foreign, on the Microscope and its 

 Uses, have seemed to the Author fully adapted to meet this 

 demand (some of them being almost exclusively concerned with 

 the Microscope itself, and others with some special branch or 

 branches of Microscopic study), he has felt encouraged to carry 

 out a plan which he had formed several years since; by endea- 

 voring to combine, within a moderate compass, that information 

 in regard to the use of his "tools" which is most essential to the 

 working Microscopist, with such an account of the objects best 

 fitted for his study, as might qualify him to comprehend what 

 he observes, and might thus prepare him to benefit science, 

 whilst expanding and refreshing his own mind. 



In his account of the various forms of Microscopes and Acces- 

 sory Apparatus, the Author has not attempted to describe eveiy- 

 thing which is in use in this country; still less, to go into details 

 respecting the construction of foreign instruments. He is satis- 

 fied that in all which relates both to the mechanical and the 

 optical arrangements of their instruments, the chief English 

 Microscope-makers are decidedly in advance of their Conti- 

 nental rivals ; and on this point he speaks not only from his 

 own conviction, but from the authority of a highly accomplished 

 German Microscopist, who has recently visited London for the 



