CONVERSION OF NUMBERS FROM ONE SCALE TO ANOTHER. Jgl 



(B) About two ounces of the filtered liquor were exposed Crystals of ox- 

 to a temperature below ebullition (however from inattention mal'^^' (T'' 

 the liquor boiled about two minutes) until evaporated to 

 about one sixth. This evaporated liquor on cooling was of 

 the consistence of a sirup, and amongst it a few small qua- 

 drilateral prismatic crystals could be observed ; it smelled 

 something like burnt sugar, tasted not very acid, was rea- 

 dily soluble in water, the solution aliording with lime water 

 a slowly deposited white flocculent precipitate, almost com- 

 pletely soluble in vinegar. Hence I infer this evaporated 

 siruplike product to be principally malic acid; and the few 

 crystals observable, oxalic acid. 



From the results of No. 4 I think it but fair to conclude, No peculiar 

 that the acids produced by the mutual action of nitric acid ^-"^ ^" g'^g^J^- 

 and ginger root are the malic and the oxaiic; the latter, 

 as is the case with many other vegetable substances, the 

 result of a more complete reaction of the elements of the 

 two agents ; and this conclusion may be more readily ad- 

 mitted, when it is considered, that Exp. I, 2, 3, in no 

 manner argue against it. 



IV. 



On the Method of transforining a Number from one Scale of 

 Noialion to another, and its Application to the Rule of 

 Duodecimals, By Mr. Peter Barlow. 



I 



To Mr. NICHOLSON. 

 SIR, 



r is rather the novelty, than the utility, of the rules q,^ tr n f 

 contained in the following paper, that has induced me to ring numbers 



send it for insertion in the Philosophical Journal, thouyh it from one scal« 



... ,. , , ^ ■ f. ■ to another, 



may possess some little or the latter; and il it will not ex- 

 clude matter of more interest, it may probably be accepta- 

 ble to some of your mathematical readers : in which case it 

 is very much at your service. 



Yours, &c. 

 Royal Military Academy, Woolwich, P. BAB-LOW. 



Jan. 29th, 1810, 



Before 



