iv PREFACE 



The very apparent need of including a course in the manip- 

 ulation and applications of the microscope in the curriculum of 

 students of chemistry led to the establishment, by the author, 

 of laboratory courses in chemical microscopy some fifteen years 

 ago. These courses have comprised informal lectures, demonstra- 

 tions and laboratory practices. The students have been guided 

 by their notes and by mimeographed and typewritten sheets. 

 With the growth of the courses in number of students, apparatus 

 and laboratory equipment, some more permanent and compre- 

 hensive outline has become imperative. The result has been 

 the preparation of the present little book. The author has 

 intended it primarily for his students in elementary chemical 

 microscopy and as a basis for more advanced work in specific 

 fields, but he hopes that the gathering together of methods 

 and apparatus may prove of value to American chemists at 

 large and perhaps serve to arouse in some an interest in one of 

 the most fascinating branches of chemical science. 



The actual nucleus about which the various parts of the book 

 have grown is a series of some twenty articles written by the 

 author between the years 1899 and 1902 for the Journal of Applied 

 Microscopy, dealing with methods of microchemical analysis; to 

 this foundation have been added the laboratory direction sheets 

 and the substance of the lectures delivered. 



Until the year 1911, when Emich's excellent little Lehrbuch 

 der Mikrochemie appeared, there was not in existence any work 

 embodying the broad applications of the microscope to the 

 solving of problems such as arise in the chemical laboratory. 

 So far as the writer is aware this is the only book touching this 

 field. The topics presented by Emich are substantially those 

 which have been covered in the author's courses with the excep- 

 tion that more weight is placed upon analytical methods and 

 less upon apparatus. The present writer therefore feels that 

 there is still room for an outline of Chemical Microscopy proper. 



It is assumed that the students for whom this textbook is 

 intended have had a course in crystallography and one in physics, 

 including optics. Therefore, only a mere statement of funda- 

 mental facts has been thought essential, that is, only so much 



