3'34 Analyfis of the Honey -J} one, or Mellite. 



bonic acid, that of water, and the fmall portion of charcoal 

 which the mellite furnifhes by diftillation, arc all facts which 

 feem to concur to prove the identity of thefe two acids ; for 

 the fait of forrel exhibits in the fire the fame phenomena*. 



The o&aedral form of the mellite feems alfp to have an 

 analogy with that of the oxalic acid, which is a rectangular 

 prifm terminated by pyramids of four faces : to be certain of 

 this, nothing is neceflary but to compare the inclination of 

 the faces. 



However, as I had at my difpofal only about 1-34 gramme 

 of this acid, I was not able to fubjecl: it to all the tefts necef- 

 fary to demonftrate, in a pofitive manner, its identity in every 

 point with the oxalic acid ; for, though they exhibited ana- 

 logous phenomena in all the comparative experiments I 

 made, it is- poffible that by others which may be made 

 hereafter there may occur one difference fufficient to deftroy 

 the refemblance. 



I have therefore publifhed this notice chiefly with a view 

 of inducing the chemifts of Germany, where this fubflance 

 is moll commonly found, to repeat the analyfis of it, and to 

 compare, under every point of view, its acid with that of 

 forrel. Should my opinion be confirmed by new experi- 

 ments, we (hall then have oxalic acid in the three kingdoms 

 of nature, viz. in the (late of acidulous oxalat of potafh in 

 Fpveral kinds qJF vegetables j in that of oxalat of lime in hu- 

 man urinary calculi ; and, in the lad place, in the flate of 

 oxalat of alumine in the interior of the earth among bitu- 

 minous kinds of wood ; but, in whatever place found, it feems. 

 always to be indebted lor its origin to vegetable matters f. 



X. Dr< 



: * The acid of forrel, or oxalic acid, is that which furnifhes by diftilla- 

 tion the largeft quantity or cproonic acid and water; becaufe, of all tho 

 natural vegetable acids known, it contains moft oxygen, 



f Since the above paper was written, I conceived the idea of mixing 

 the acid of honey-ftone, united to a little potafh, with a folution of pure 

 fulphat of alunyne, and there was immediately formed a very abundant 

 flaky depofit: or. the other hand, I put into a folution of the fame fak 

 acidulous oxalat of potafh, but there were no figns of precipitation. 



Thefe different efie&s, therefore, ought to excite well-founded doubts 

 refpectipg the identity of the acid of honey-ftone and the exalic acid ; and 



I cogfi.fi 



