PREFACE. 



The American chemist, usually ready to accept with alac- 

 rity all time, labor and money saving devices, has been strangely 

 backward in taking advantage of the benefits to be gained 

 through the intelligent application of chemical microscopic meth- 

 ods in the industries and in research. He has also failed to 

 grasp the fact that the modern microscope is, in reality, a more 

 important adjunct to his laboratory than spectrometer, polarim- 

 eter or ref ractometer ; in fact, it may be said that the micro- 

 scope is entitled to as important a place as the analytical balance. 

 No one other instrument can perform so many functions and do 

 them all well. 



This curious reluctance to grasp the opportunities offered is 

 the more extraordinary, when we recall that the earliest com- 

 prehensive work dealing with microchemical methods was from 

 the pen of an American Theodore G. Wormley whose 

 classic "The Microchemistry of Poisons" appeared in 1867. 



The failure of the chemists to obtain from the microscope all 

 that the instrument is capable of yielding is, perhaps, largely 

 due, first, to the fact that few of them are given an opportunity 

 of becoming sufficiently familiar with the instrument and its 

 accessories; second, they are not aware of the great variety 

 of problems which are solvable through the microscope, nor of 

 the specific sort of problems for the investigation of which this 

 is the instrument par excellence; third, there has been a lack of 

 elementary manuals covering the field, and for this reason the 

 microscope has been looked upon as an instrument peculiar to 

 the biological laboratory. 



One application, if no other, should appeal to every chemist, 

 that of microscopic qualitative analysis, because of its enormous 

 saving of time, labor, material and space, yet with increased 

 sensitiveness of tests and greater certainty of results. 



