I 



OUTLINE OF MICRO-ANALYTICAL METHODS IN 

 FOOD AND DRUGS LABORATORIES 



I. Introduction 



The value of the compound microscope in the examination of 

 foods and drugs is as yet not generally recognized. 'Efficiency in 

 this line of work depends very largely upon a long and wide range 

 of experience, in this regard differing very markedly from effi- 

 ciency in the field of chemical analyses. All that is required of 

 the chemist, as far as routine analytical work is concerned, is a 

 very close adherence to the methods laid down for him. He is 

 pronounced skilled in direct proportion to his adherence to 

 methods and skill shown in the manipulation of apparatus and 

 reagents. The micro-analyst in order to be efficient must be very 

 familiar with the appearance of the multitudinous forms of cells, 

 tissues, cell-contents and with the behavior of certain micro- 

 chemical reagents and this familiarity can be acquired only through 

 long and careful observation. 



2. Grouping of Substances to be Examined in Food and Drugs 



Laboratories 



The analytical methods, as they apply to the critical examina- 

 tion of foods and drugs, are chemical, microscopical and bacteriolog- 

 ical. The substances to be analyzed may be grouped as follows: 



