FOODS AND DRUGS AND THEIR ADULTERANTS. 73 



channels {A, Fig. 29). The first two tissues appear, as a 

 rule, as large opaque dark-brown masses, with the cell 

 structure showing only at the edge. 



The detection under the microscope of other cell 

 structures than those mentioned at once serves to indi- 

 cate the presence of adulterants. Leach has pointed out 

 that even a naked-eye examination sometimes reveals 

 foreign substances. "The chicory grains are apparent 

 from their dark and somewhat gummy appearance, and 

 can usually be recognized by crushing them between the 

 teeth. Their soft consistency and bitter taste are very 

 distinctive. The dull surface of the outside of the 

 crushed coffee-grains is in marked contrast to the pol- 

 ished appearance of the surface of the broken peas or 

 beans, often to be found as adulterants, while fragments 

 of broken cereal grains are readily distinguished from 

 coffee with a low-power magnifier, though perhaps not 

 easily identified by the eye alone." 



4. Chicory and other Adulterants of Coffee. — ^The 

 roasted root of Cichorium Intybus is one of the substances 

 most commonly found mixed with coffee. Its presence 

 is at once betrayed by the appearance of masses of tissue 

 made up of elongated cells of the type common to the 

 stems of the higher plants. The outer layers are thin- 

 walled and delicate, while the woody tissue proper contains 

 large fusiform cells marked with fine scar-like cross- 

 hatching, the ladder-cells of the fibro-vascular bundles. 

 Occasionally, too, particles will be found which show the 

 very peculiar branching, tubular structures of a homo- 

 geneous dark color, which are known as the milk-tubes. • 



