5 J<5 Analyfis of the Mdliit er Honigjlein. 



The fecond had for his refult 86.4 of charcoal, 3.5 petroleum, 2 filex, and 3 of water 

 of cryflallization. An enormous difference *. 



Mr. Abich propofes on account of the incombuftibility of the honigftein, that it {hould 

 be removed from the clafs of combuftlbles, and placed in that of the alumines. 



But Mr. Klaproth, whofe labours arc intitled to thehigheft confidence, wrote me fe- 

 veral months ago, that he has difcovered that this pretended ftone is compofed of a pecu- 

 liar vegetable acid united to alumine. 



M. Abildgnaard, to whom I am indebted for many interefting minerals of Norway, fent 

 me fome decades ago, by favor of M. Mantey, a fmall quantity of honigftein, of which he 

 had dcfigned part for analyfis : and I haftened to comply with his wifh in that refped. 



Defcrlption of the Honigjlein, 



This fubflance has a light yellow colour, which has caufed it to obtain the name of 

 mellite, or honey ftone. It is ufually cryftallized in an o£lahcdron, of which the angles 

 are fometimes replaced by faces, cwing to laws of diminution, of which the laws have not 

 yet been limited. 



Its fpecific gravity is not confiderable. It is according to M. Abich i. 666. It is found 

 in Thuringia in ftrata of foffil bituminous wood. 



I. Chemical CharaEier of Honigjlein. 



When expofed to fire with the contact of air it becomes white, and burns without be- 

 coming fenfibly charred ; it leaves a white matter, which produces a flight efFervefcence 

 with acids. It has no fenfible tafte 5 though if it be kept for fome time on the tongue, it 

 occafions a flight impreflion of acidity. 



II. ANALYSIS. 



I took two grammes of the honigftein reduced to powder, and mixed them with four 

 grammes of faturated carbonate of pot-afti diflblved in a fufficient quantity of water. As 

 foon as the mixture was made, an efFervefcence of confiderable aftivity followed, witho^it 

 the aflUftance of foreign heat ; but to accelerate, and more efFe£lually to complete the de- 

 compofition of this fubftance, I flightly heated it on a fand bath. 



The filtered liquor after cooling was of a brownifh colour, and left on the filtering paper 

 a brown matter, which when dried in the fun weighed very nearly 0.8 of a gramme. 



* If M. Lampadius operated upon the fame fubftance as Mr. Abich and m^ifelf have analyzed, it is 

 Hnpolllble he coujd have had 86.4 of carbone j for in forty parts of carbonic acid, and four of carbone, ob- 

 tained by Mr. Abich, there is not the matter to form eighty-fix of carbone : and as from my analyfis it 

 appears to me that there is not more than 55 per cent, of real acid in the honigftein, it is evident that it. 

 cannot afford eighty-fix of charcaal. It muil therefore necelTarily follow, either that Mr. Lampadius did 

 opei-ate upon another fublVance, or that he ^d not heat it fulSciently to decompofe the acid, if he did is. 

 Caftoperate upon the hoqigftein. 



This. 



