168 On alloying Iron with Manganese. 



the keesh of No. I. pig-iron unacted upon. The metallic but- 

 ton was covered with a splendid coating of plumbago of the co- 

 lour of silver. The globules were equallv carburetted, but still 

 magnetic. The whole weighed 276 grains, which is e([ual to 

 55-jij- per cent. If the produce of the ore is taken at 50, 

 which is near truth, then an allov of metallic manganese of 

 nearly 5| parts with 50 of iron was foruied — a higher combina- 

 tion than any hitherto obtained in these experiments : the in- 

 crease of metallic weight beyond a produce of 50 per cent, is 

 26 grains. This being obtained from 200 grains of manganese, 

 is a produce from this ore of only 13 per cent. A slight diminu- 

 tion of magnetic influence was perceptible in part of the metal- 

 lic result of this experiment. 



5th Exp. Iron ore .. .. .. .. 500 grs. 



Roasted ore of manganese . , . . 300 



Chalk 400 



Glass .. 500 



Charcoal . . , . . . . . 160 



This mixture was also perfectly fused. The surface of the 

 glass was not, as in No. 4, covered with shining carburet, but 

 with a rough cream-coloured porcelain minutelv punctured and 

 in some instances crystallized. Beneath, a tran-^parent smoky- 

 coloured glass was found, verv different from common assay- 

 glasses of iron. The metallic button and globules were covered 

 with the same coating of plumbago described in the last experi- 

 ment. Weight 290 grains, or 58 per cent. Increase beyond the 

 product of the iron ore 40 grains, which from 300 grains of ore 

 of manganese is 13-]- per cent. Gained over last experiment only 

 4 per cent. 



6th Exp. Iron ore . . . . . . . . 500 grs. 



Roasted ore of manganese . . . . 400 



Chalk 400 



Glass 500 



Charcoal 160 



From the fusion of this mixture a singularly composed glass 

 appeared: the surface was stony, of a whitish colour, covering a 

 stratum of similarly coloured porcelain. Beneath a fine trans- 

 parent glass interspersed with circular concretions of crystallized 

 porcelain, only tvvo grains of shining carburet were found un- 

 acted upon. The metallic button and globules were equally 

 shining and carburetted with the former experiments, and weighed 

 318 grains; which is a produce of 63-^?,-, per cent, from the iron 

 ore ; which being a gain of 68 grains of metal beyond the assay 

 produce of the iron ore, makes the yield of 400 grains of man- 

 ganese equal to 17 per cent. This metallic alloy wiU therefore 



be 



