PART II 



THE MICROSCOPICAL CHARACTERISTICS OF THE 

 VEGETABLE POWDERS 



In order that the student may take up the critical study of pow- 

 dered vegetable drugs as to quality and purity, he must have the 

 necessary preparation. Such preparation is given in the courses in 

 general botany, in plant morphology and histology, and in pharma- 

 cognosy, as presented in the first and second years of the college 

 curriculum. 



The significance of the adulteration of drugs has been explained in 

 Part I. Throughout the examination of the powders listed in Part II, 

 the student is urged to search for the foreign inclusions which may be 

 present and to record these descriptively and by means of drawings. 

 The first thing to be accomplished is to acquire the ability to recognize 

 foreign inclusions, after which the special training must be directed 

 along the following lines. 



1. To recognize those inclusions which are wholly unavoidable. 



2. The wholly negligible inclusions. 



3. The usual or more or less normal sophistication and 

 adulteration. 



4. Conventional sophistication. 



5. Unquestionable sophistication and adulteration. 



As to (1), the student will soon learn that all crude as well as 

 powdered vegetable drugs contain some foreign substances, as dirt 

 and sand particles, some bacteria, occasional spores and pollen grains, 

 a trace of foreign vegetable tissue, occasional nematode or insect, 

 remnants, etc. Even the gum tragacanth contains some starch; 

 the highest grade cloves contains a small amount of stem tissue; 

 the best quality black pepper contains some pepper refuse; the best 

 chocolate and cocoa contains some shell tissue; and the purest coffee 

 contains some coffee chaff. These are among the wholly unavoidable 

 inclusions and which may not be considered as adulterants. 



As to (2), it is common knowledge among dealers in drugs and 

 those who use drugs for manufacturing purposes, that certain more or 

 less accidental and unavoidable inclusions are always to be found in 

 crude as well as in powdered vegetable drugs, and which inclusions are 

 generally considered so small in amount as to be wholly negligible. 

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