24 DECOMPOSITION OF BORACIC ACID. 



Attempt to ob- As the chocolate coloured substance is permanent in wa- 

 colate coloured ter ' n occurred to rne, that it might possibly be producible 

 substance frmn concentrated liquid fluoric acid at thy negative surface 



in the Voltaic circuit, 

 from the acid 1 made the experiment with platina surfaces, from a bat- 

 expenTdliT ter J °^ two nun d re d ai1 ^ fifty plates of six inches, on fluoric 

 the sulphuric acid the densest that could be obtained by the distillation of 

 sel en ves * fluor spar and concentrated sulph uric acid of commerce in 

 vessels of lead. Oxigen an: hi Lrogea were evolved, and a 

 dark brown matter separated a. the deoxidating surface; but 

 the result of an operation conducted for many hours merely 

 enabled me to ascertain, that it was combustible, and pro- 

 duced acid matter in combustion; but I cannot venture to 

 draw the conclusion, that this acid was fluoric acid, and it 

 was not impobsible, that some sulphurous or sulphuric acid 

 might likewise exist in the solution. 



Olive coloured | heated the olive coloured inflammable substance, ob- 

 substance from , _ ,11 ■ • 1 • <* ■ ■ ■, 



boracicacid tamed from the boracic acid, in common fluoric acid gas in 



heated in fluo- a plate glass retort ; the temperature was raised till the glass 



' began to fuse ; but no change, indicating a decomposition, 



took place. 



Potassium and I heated six grains of potassium with four grains of povv- 



fluor spai- dered fluorspar in a green sdass tube filled with hidroaren ; 

 heated in hi- .,-... b . -*..«. 



drogen. there was a slight ignition, a minute quantity of hidrogen 



gas was evolved, and a dark gray mass was produced, which 



acted upon water with much eii'ervescence, but left no solid 



inflammable residuum. 



(To be concluded in our next. J 



III. 



Remarks on the Boracic Acid, addressed to the first Class of 

 the ln'stisute, December the 19th, 180y by F. R. Curatj- 

 d au , Professor of Chemistry applicable to the Arts, and 

 Member of several literary Societies*. 



HP 



If boracic acid JL HE process, by which Messrs. Thenardand Gay-Lussac 



b» ^tLShmf ' iave announced, that they decomposed the boracic acid, 



by potassium 



* Journal de Physique, March, 1309, p. 256 



though 



