162 POWDERED VEGETABLE DRUGS 



Standard insect Compared insect 

 powder powder 



Pollen grains 5.4 0.2 



T-shaped or spindling hairs 2.0 2.1 



Sclerenchyma cells 10 . 0.6 



Fibrous tissue 8.0 60.0 



The findings would indicate that the article in question was 100 

 per cent, adulterated and that the adulterant was Pyrethrum stems. 

 The small amount of pollen found in the compared article may be 

 wholly ignored as that amount of pollen is normally present in and 

 upon leaf and stem tissue, even though no flowers are present. A 

 so-called insect powder may show abundant pollen grains and yet be 

 100 per cent, adulterated, as when foreign flowers are used, hence the 

 analyst must be able to recognize different pollens. 



Sample powdered Clove stems 

 cloves 



Bast cells of clove stems 6.0 10.0 



Sclerenchyma cells 12.0 21.0 



In the above example the comparison is made with pure clove 

 stems, which article is the most common adulterant of powdered cloves 

 and in this case the two tissues, namely bast 'and Sclerenchyma, are 

 present in fairly constant ratio, hence both counts may be used and 

 should check each other, if carefully made. The double proportion 

 would be 10 : 6 :: 21 : 12 :: 100 per cent. : x per cent. lOz = 600 = 

 60 per cent. 2lx : 1200 = 58 per cent. Under the law (fed- 

 eral pure food and drugs act) 5 per cent, of stems are allowed. Sixty 

 per cent, less 5 per cent, leaves 55 per cent, unlawful adulteration in 

 this case. In this case the average of 60 per cent, and of 58 per 

 cent-., namely, 59 per cent, should be taken. 



Sample cocoa Cocoa shells 



Fragments of spiral ducts 3.8 13.9 



Sclerenchyma cells 2.6 10 . 



The spiral ducts are most readily recognized and are fully as diag- 

 nostic as the Sclerenchyma cells. Both tissue elements should be 

 included in the counts and the average of the two percentages ob- 

 tained should be used. Thus, 13.9 : 3.8 :: 10.0 : 2.6 :: 100 per cent.: 

 x per cent. 13.9z = 380 = 20.1 per cent., and Wx = 260 = 26 per 

 cent. 20.1+26-i-2 = 23.05 per cent, of shells in the cocoa under exam- 

 ination. Under the law 3.50 per cent, of shells (called "crude 

 fiber") is allowed, hence in the above case we have 23.05 3.50 = 

 19:55 per cent, of excess of shells or crude fiber. The starch count is of 



