PREFACE 



This book is intended as a guide to the use of the microscope. 

 The correct use of the instrument follows directly from a know- 

 ledge of the functions of the difierent parts. It has therefore 

 been found best to develop the method of manipulation in the 

 course of the descriptions of the component portions. Such 

 particulars as are given of the principles of its optical construc- 

 tion are of the simplest character, and their comprehension 

 requires no optical knowledge. Certain theoretical matters 

 are stated in this book, but are not explained. Some of the 

 descriptions may appear to be extremely elementary to experi- 

 enced mieroscopists, but it is hoped that even they may find useful 

 matter which is not available in the ordinary text-books. 



The author hopes to publish a further volume at a later date, 

 which will deal with the optical theory and the use of the 

 microscope in greater detail. 



