Intelligence and Miscellaneous Articles. 



313 



if the clav newly discovered beneath the quarries be added to the 

 series, it will form another subdivision, accordant with the principle 

 of arrangement above mentioned. The chief question remaining 

 with respect to this lowest group of marine clay is, whether it will 

 be necessary to detach it altogether from the other divisions of the 

 lower greensand ; and this cannot be decided without a deliberate re- 

 view of the subcretaceous fossils, — and of the strata which afford 

 them. 



XLVII. Intelligence and Miscellaneous Articles. 



EXPERIMENTS ON COFFEE. 



To the Editors of the Philosophical Magazine and Journal. 

 Gentlemen, 

 fTlHE object of the present communication has reference to some 

 J_ experiments on coffee which I think possess some novelty, if 

 they have no other merit. It is well known that this article during the 

 process of roasting loses from 19 to 25 per cent, of its weight, this 

 is principally water evaporated at the very high temperature it is ex- 

 posed to. I speculated that if this moisture could be previously 

 withdrawn, without the application of heat, a much shorter exposure 

 to a high temperature would afterwards be required to complete the 

 process, and that an equivalent improvement in the quality might be 

 looked for. 



To test this I accurately weighed two packages of the same Ja- 

 maica coffee, each containing 8 ounces ; one package, made up in 

 paper, I inclosed in a jar with a very close cover, containing a quan- 

 tity of fresh-burned quicklime ; the second package I kept by me ; 

 I anticipated that the lime would attract the moisture from the in- 

 closed air, and that the air would in its turn take the moisture from 

 the coffee. After two months I opened the jar ; the coffee did not 

 appear shrunk, and was but very slightly altered in colour, but on 

 weighing it I found it reduced to 6£ oz., thus showing a loss of nearly 

 15 per cent. I separately roasted the two samples; the one I had 

 kept by me still weighed 8 oz. ; it took the usual time, and when 

 weighed was 6£ oz. ; the second sample had scarcely been raised to 

 the required temperature when it suddenly swelled, and the process 

 was complete in much less than one third the usual time ; when 

 weighed it was 6| oz. The following Table will give a synopsis ; 

 No. 1 is the coffee that was treated with lime : — 



It will be observed that the sample No. 1 weighed more after 

 roasting than No. 2. Part of this increase might have been caused 

 by the latter being a little more highly roasted, but I am confident 

 that this would not account for so great a difference in so small a 

 quantity. The two samples were now ground and prepared in the 



