Analysis of Iron Ores, &c\ 



[ie like a stiff plank, and rather to occasion a thrust 



than otherwise, which when the weight has 



| may be again raised by the same operation. 



ilks ace now to be laid on to meet at the intervals as 



hnograpbic plan O, of which P is the elevation 



ripletc. O is a perspective view of three joints looking 



the bridge with the planks, &c, drawn faintly. 



III. Analysis of some Iron Ores in Burgundy and Franchc- 

 ComtC' ; to which is added an Examination of the Pig 

 Iron, Bar Iron, and Scoriae, produced from them. By 



M. \'Al*aUKLLN *. 



In the year 1805, M. Vauquelin having visited various iron 

 works in Burgundy, collected specimens of ores, pig iron, 

 bar iron, scoria, and fluxes; intending to subject them to 

 chemical analyses, to ascertain whether it might be possible 

 to learn, from a comparison of their composition, what 

 takes place in the processes to which iron ores and cast iron 

 are subjected. The following are the principal results of this 

 able chemist's labours, and the particulars of some of the 

 processes he employed to obtain them. 



I. Chemical Exaimnatmi of some Fluor Spars. 



The spar used as a (lux at the mine of Drambon, -in the 

 department of Cote-d'Or, is yellowish white, and tolerably 

 hard. It dissolves with effervescence in nitric acid, and 

 leaves a yellowish residuum, amounting to about a fifth of 

 its weight, which is composed chiefly of fine sand, with a 

 minute quantity of alumine and iron. The solution, which 

 is colourless, gives with ammonia a light, fiocculcnt, semi- 

 transpaienf, yellowish- white precipitate, in which was de- 

 lected iron, a little alumine, and phosphate of lime. It 

 likewise exhibited some traces of silex. 



The spar of Pesine is compact, of a grayish white, and' 

 dissolves in nitric acid, leaving a residuum of about a Iwen- 



* From Journal det Minn, No. I 19 — being an abr'dgment of a paper 

 'given ux the Memoirs of the National Institute. 



ticth 



