1 08 Of Coffee, and the Art of preparing it. 



—-siri.rad. Now, Ifet n= — , m being; a large positive 



whole number; the oos. ?z9 will differ very little from unit, 

 or r will very nearly equal I» between the limits 9 = 0, and 



■r 2'" "•" ' 90" 



Q = -- V, within which limits S= — -— X R' x sin. — 



which is aloebraic, because siri. — may be expressed al- 



gebraically; and this value of S very nearly equals — R', 



as the problem requires. 



I am, sir, 



Your obedient servant, 



X.Y. 



XVII. Of Coffee, and the Art of preparing it. Extracted 

 from Count Rumford's Eigkteenth Essay. 



J- HE author remarks that, "among the numerous luxuries 

 of the table, unknown to our forefathers, coffee may be 

 considered as one of the most valuable. Its taste is very 

 agreeat)le, and its flavour uncommonly so j but its prin- 

 cipal excellence depends on its salubrity, and on its ex- 

 hilarating quality. It excites cheerfulness, without intoxi- 

 cation ; and the pleasing flow of spirits which it occasions, 

 lasts nianv hours, and is never followed bv sadness, languor^ 

 or debility. It diffuses over the whole frame a glow of 

 health, and a sense of ease and well being which is ex- 

 trenielv delightful : existence is felt to be a positive enjoy- 

 ment, and the mental powers are awakened, and rendered 

 uncommonly active." After some other judicious obser- 

 vations on the valuable properties of ctjffee, and the un- 

 certainty of the result in the common methods of preparing 

 it, the Count proceeds with his subject. 



" Different methods have been employed in making 

 coffee; but the preparation of the grain is nearly the same 

 in all of them. It is first roasted in an iron pan, or in a 

 hollow cvlindcr made of sheet-iron, over a brisk fire; and 

 when, from the colour of the grain, and the peculiar fra- 

 grance which it acquires in this process, it is judged to be 

 sufficientlv roasted, it is taken from the fire, and suffered 

 to cool. When cold it is pounded in a mortar; or ground 

 in a hand-mill to a coarse powder, and preserved for use. 



*' Great care must be taken in roasting coffee, not to 

 roast it too much : as soon as it has acquired a deep cin- 



namoxi 



