ON THE BORACITE. J2l 



Citizen Vauquelin having examined this fubftance fome 

 time ago with Mr. Smith, who brought a confiderable quan- 

 tity, thought himfelf juftified in concluding, that the lime is no 

 eflential part in its composition, becaufe its powder effervefces 

 with the acids, and the fmall quantity of lime which chemifts 

 find in their analyfis, did not appear to exceed that which the 

 degree of effervefcence has fince indicated. They then at- 

 tempted, by weak acids diluted with much water, particularly 

 by the acetous acid, to feparate the portion of carbonate mixed 

 with the borate ; but they did not fucceed, becaufe the acetous 

 acid, even though feebly, likewife attacked the borate. They 

 then left the queftion undecided, for want of tranfparent cryf- 

 tals which did not effervefce with the acids. 



But fince that period, Mr. Stromager having fupplied Citi- 

 zen Vauquelin with cryftals of this defcription, perfectly tranf- 

 parent, he fubjedted them to new experiments, with the inten- 

 tion merely of afcertaining the'prefence of lime. 



He mixed their powder with muriatic acid, and when the Experiments 

 folution was effected by means of a gentle heat, he evaporated ™ hlc . h Aew cha * 



, , /• • , i , r r - i ^ r , "me is not an 



to dryneis in order to expel the excels or acid, and afterwards eflential part of 



dillblved it in a fmall quantity of cold diftilled water. By this this mineral. 



method he feparated mod of the boracic acid, which was in 



very white brilliant plates. He diluted the folution with water, 



and mixed a certain quantity of oxalate of ammonia, which, 



as chemifts know, is the befl re-agent to fliew the prefence* of 



the fmalleft quantity of lime contained'in any fluid, provided it 



contain no excefs of acid. Neverthelefs, it exhibited no fign 



by which the exiflence of that fubftance could be fufpedled. 



In order to afcertain that the fmall quantity of boracic acid 

 dillblved by water, at the fame time as the muriate of magnefia, 

 did not oppofe the precipitation of the lime, he mixed a portion 

 of the muriate of lime, which did not certainly amount to a 

 fiftieth part of the borate employed, and a cloud was immedi- 

 ately produced through the whole of the fluid. 



On the other part, he decompofed the artificial borate of 

 lime in the fame manner as the natural borate, and obtained, 

 by the addition of oxalate of ammonia, a very abundant preci- 



It is therefore evident, that if the natural borate had contain- 

 ed only one hundredth part of its weight of lime, it would have 

 given fome indication by the methods employed by C. Vau- 

 quelin 



