72 



BRITISH COFFEE. 



The seeds de 

 •cribed. 



Iffects of 

 roasting. 



80 very similar to what take place in foreign coffee during 

 the same process, that I shall presently relate them. 



The seeds of the iris pseudacorus when ripe, fresh ga- 

 thered, and freed from the husks, are of a dirty brown cor 

 lour, semitransparent, and tough like horn. They have, if 

 I may be allowed the expression, a leguminous taste. Their 

 form is various, some are circular and thin, others wedge 

 shaped, while others again are conical* resembling minute 

 bulbous roots. They are between three and four lines in 

 breadth, never more than four, and they are seldom more 

 than two lines in thickness, but generally much thinner. 



Beside the arillus, which merely covers the crown of the 

 seed, it is closely enveloped by a very thin brown epidermis, 

 which firmly adheres to the rugous surface of the seed, giv r 

 ing it the appearance of very fine shagreen. When this 

 covering is removed, the seed itself is of a yellowish colour. 

 Under the microscope this epidermis appears to consist of a 

 congeries of papillae distilling an oil from the surface of the 

 seed underneath *. 



When the seeds are exposed to heat upon an iron plate, 

 in order to roast them, they at first crackle and are covered 

 with minute blisters, they change to a reddish brown colour, 

 and are rendered opake ; they next become dark brown, and 

 almost black, by the carbonization of the epidermis; they 

 now sweat, or appear oily, emit a dense smoke, and acquire 

 the aromp of coffee. If they be taken from the fire at this 

 stage of the process, and wrapped in unsized paper, it ab- 

 sorbs the oil, and different parts of it thereby become trans- 

 parent. 



In this state the epidermis, though carbonized, does not 

 easily separate from the seed, but adheres to its oleaginous 

 surface, giving it a very dirty appearance. But if rubbed 

 in a cotton or woollen cloth, or tossed to and fro in a bag 

 but partly filled with them, they may be freed from this 

 carbonaceous matter, and will thus receive a polish that 

 will enable them to bear handling without staining the fin- 

 gers. 



• The arillus, the epidermis, and even very thin cuttings of the seed 

 itself are exceeding beautiful microscopic objects. 



If 



