CHAPTER II. 

 POWDERED VEGETABLE DRUGS AND FOODS. 



Inasmuch as a large proportion of vegetable drugs frequently 

 occur in the market in a powdered or ground condition, it becomes 

 of first importance to be able to identify them, as well as to deter- 

 mine their quality in this form. Without a microscopical exam- 

 ination or chemical analysis this would then depend on such 

 factors as color, odor and taste. With some drugs an estimation 

 of quality based on these properties would be of more or less 

 value, particularly those containing aromatic and bitter principles ; 

 yet it would soon be found that a more detailed examination 

 would be required to determine their degree of purity or even to 

 identify them with certainty in all cases. 



Classification. It was not considered desirable to give a 

 detailed description of the powder under each drug in the chapter 

 on crude drugs, for the reason that the identity of the drug as a 

 root, rhizome, bark, etc., is lost, and in the examination of a 

 given powder it is usually found advantageous to compare it with 

 those powders having a similar color. By a careful comparison 

 of the powders of the vegetable drugs, it has been found that 

 according to their colors they form five main groups, as follows : 

 (i) Greenish powders, (2) yellowish pow^ders, (3) brownish 

 powders, (4) reddish powders, (5) whitish powders. These 

 groups are then subdivided according to the kinds of cells and the 

 nature of the cell-walls and cell-contents. . 



Adulterants. Powdered drugs are frequently adulterated 

 either by the use of wheat middlings or by the use of exhausted 

 powders, i.e., those from which the active or important consti- 

 tuents have been extracted. The following examples serve to 

 illustrate the methods in use : Powdered cloves are occasionally 

 admixed with the exhausted powder, or the exhausted powder 

 alone, to which a small quantity of oil of cloves and some color- 

 ing matter are added, is sold as powdered cloves. Exhausted 

 gentian, to which has been added a small quantity of a bitter 



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