101 



the coffee be pure, it for the most part floats, becomes very 

 slowly moistened, even when shaken up with the water, and 

 communicates scarcely any colour to the liquid ; very gra- 

 dually ifc imbibes water; the liquid acquires a very pale 

 sherry tint ; and at the end of several hours the greater 

 part of the powder is found to have fallen to the bottom of 

 the glass. If, however, it be chicorised, the presence of 

 chicory (genuine or spurious) will be readily detected, by a 

 portion of the suspected powder rapidly sinking and commu- 

 nicating to the liquid a reddish-brown tint, which will be more 

 or less deep according to the amount of chicory present. 



If the coffee be adulterated with what is called Hambro' 

 powder (roasted and ground peas, &c., coloured with Vene- 

 tian red) or roasted corn, we have a further test in iodine, 

 which communicates a purplish or bluish-red tint to the 

 water to which either of these substances has been added. 

 The preceding test is sufficiently delicate and valuable, in all 

 ordinary cases, for detecting chicory in coffee ; but to those 

 familiar with microscopic investigations, the microscope 

 furnishes another mode of proceeding : fragments of dotted 

 ducts being found in chicory, but not in pure coffee. They 

 are not met with, however, in great abundance ; and some 

 patience and care, therefore, are requisite in searching for 

 them. The starch grains of Hambro' powder are readily de- 

 tected by the microscope, as also the blackening effect of a 

 solution of iodine on them. 



Plate 10 represents the structure and character of genuine 

 ground roasted coffee, and of a fragment of roasted chicory- 

 root, showing the dotted or interrupted spiral vessels which 

 pass in bundles through the central parts of the. root, mag- 

 nified 140 diameters ; copied, by permission, from Dr. Has- 

 sall's work on " Food and its Adulterations." 



In the raw chicory-root three parts or structures may be 

 distinguished with facility, cells, dotted vessels, and vessels 



