New Prucejis for Aimlyfng Steel, 21^; 



To estrad this combuftible fubftance from the carbure of iron, I heated the mixture flightly 

 with a folution of cauflic pot-alh; and having left the matter to fettle, I decanted the fluid. 

 The powder, then, after wafhing and drying, weighed no more than four grains, and gave 

 no further figns of fulphur by combuftion *. This experiment evidently proves, that in 

 the experiment No. i, where fulphuric acid was ufed, the greateft part of the carbone was 

 diflblved, and carried off by the hydrogene gas, fince 576 grains afforded only I,g8 grains of 

 this matter ; though the fame quantity of ftcel with the fulphureous acid afforded eight 

 grains. This fteel contains therefore 0,014 of its weight of carbure of iron. 



Analyfa of the Carbure of Iron. 



Experiment V. To afcertain the quantity of carbone contained in the four grains of 

 carbure of iron obtained in the experiment No. 4, they were fubmitted to the aftion of fire 

 in a fmall porcelain faucer, under a muffle. As foon as the temperature was fufEciently 

 raifed, it took fire, and left 1,9 grains of a grey yellowilh mafs, which treated with the 

 boiling muriatic acid became white, and was reduced to 0,44 grains. 



The muriatic acid acquired in this operation a lemon colour. It afforded with very 

 pure pruffiate of pot-afli a blue precipitate, and with ammoniac reddilli flocks, which con- 

 fifl:ed of oxide of iron. The 0,44 grains of white matter infoluble in the muriatic acid, 

 prefented on examination all the characters of filex. 



From thefe experiments it follows, that the fteel No. 864, fmall piece, contains phof- 

 phorus, carbone, and filex, of which the proportion with the mafs of iron is eftablifhcd in 

 thoufandth parts in a table at the end of this memoir. 



EJfay to d'lfcover the Prefeiice of Manganefe in the Steel No. 864, Small Piece. 



Experiment VI. Bergman having announced the prefence of manganefe in all the iron 

 and fteel he examined, it became a neceffary part of my plan to examine whether this 

 metal exifted in the fteel which formed its object. Accordingly I took a known quantity 

 of the folution of 576 grains, (Experiment No. i,J from which the phofphate of iton had 

 been feparated. 1 precipitated it by well faturated pruflDate of pot-afh, to which I had 

 added a fmall portion of acid, in order that there might be no precipitation of iron in the 

 flatc of oxide. 



The wadied precipitate was then boiled with muriatic acid a littli; diluted. The mafi 

 of the matter was perceptibly diminiftied, and the liquor afl'umed a purpllflr red colour • 

 which phenomenon led me to prefume that this fteel contained manganefe. During the 

 folution or rather the ebullition of the liquor, a very perceptible fmell of pruffic acid was 

 emitted. The muriatic fluid, mixed with a folution of carbonate of potafli, afforded a 

 white jirecipitate, which became yellow by the contaft of the air. This precipitate, dried 

 by the ftove, and cxpofcd to the aflion of heat, under a mufllc, in the cupelling furnace 

 acquired a black colour.. It was igain diffolved in the muriatic acid, 'and, upon the addition 



• It appears that pot-afli sfls not only on the fulphur, but that it dilTolves alfo a portion of iron. When an 

 acid is poured into the fluid, there is found at firft a black precipitate, which is Coon followed by iinntlici 

 ■vvhitc depofitinn. This jirecipitati; being collc6ted and txamincd afforded fulphur and perceptible trices of iron. 

 'Jli'- four grains of black precipitRtc obtsiDcd in this experiment (re thcrcferc carbone in ••> pure (late, or 

 w^rly fo. V. 



of 



