408 Progress in Science. (July, 
Some experiments have been made by Mr. C. H. Morton on the condition 
in which silicon exists in pig-iron. The experiments were made on a No. 1 
Bessemer pig, containing 4°612 per cent of silicon. They tended to show that 
the silicon does not exist in a free state mechanically associated with the iron, 
but rather in a combined form as a definite silicide of iron, just as carbon may 
exist as a carbide; the silicon does not appear, however, to assume a gra- 
phitoidal form in the iron, corresponding with the uncombined carbon of 
cast-iron. 
In recently describing a mass of meteoric iron from Howard Co., Indiana, 
Dr. J. Lawrence Smith takes occasion to make some general remarks on iron, 
which are not without interest to the metallurgist. The Indiana iron appears 
to be a true meteorite; it contains 12°29 per cent of nickel, 0°65 of cobalt, and 
0°02 of phosphorus; yet when a polished face is acted on by acids it does not 
exhibit the well-known Widmannstittian figures. Some authorities have 
maintained that these markings result from the accumulation of an alloy 
richer in nickel shan the mass of the iron; whilst others have referred them 
to a definite phosphide of iron and nickel, accumulated along certain lines of 
crystallisation. Neither of these theories, however, satisfactorily accounts for 
their presence in some irons and their absence fromothers. Dr. Smith believes 
that in the solidification and crystallisation of iron there is a tendency to 
eliminate the foreign constituents to the exterior of the crystals. If, then, a 
meteoric mass has consolidated rapidly, the phosphorus might be so diffused 
as to afford no marked indication of its presence, but if consolidated slowly 
there would be a more or less perfect elimination of the phosphorus in parts 
representing spaces between the crystals of the mass. We may remark, in 
passing, that Dr. Smith has found that the presence of 1 per cent of phos- 
phorus, or less, in cast-iron, enables the metal to resist the action of concen- 
trated sulphuric acid to a greater degree than when the metal is entirely free 
from phosphorus. 
Natro-metallurgy is a term applied to a process for refining impure lead, re- 
cently introduced by MM. Payen and Roux, of Marseilles. The foreign metals 
present in the hard lead are removed by means of molten caustic soda, the 
oxidation being facilitated by the introduction of jets of steam, a blast of air, 
or addition of nitrate of soda. 
Some notes on the metallurgy of bismuth have been communicated to the 
‘‘Annales de Chimie” by M. A. Valenciennes, who describes the process 
which he has introduced at St. Denis for working the Bolivian ores. Having 
been first roasted in a reverberatory furnace, the ore is mixed with 3 per cent 
of charcoal and a flux composed of lime, soda, and fluor-spar. After reduction 
the products separate in order of density—at bottom a button of bismuth, 
above this a regulus of sulphides of bismuth and copper, and on the top a 
vitreous slag containing silicate of iron. The crude bismuth contains about 
2 per cent of antimony and lead, and about the same proportion of copper, 
with traces of silver. If used for preparation of subnitrate, the bismuth is 
fused with nitre, to oxidise the antimony, whilst the other foreign metals are 
separated by the wet way. The regulus may be roasted, and subjected to 
similar treatment as the original ore. In treating the French bismuth-ores 
recently discovered at Meymac recourse is had to a wet process. The finely- 
divided ore is digested in hydrochloric acid, the solution neutralised, and water 
added, whereby a subchloride is precipitated, and this precipitate is then 
reduced by contact with metallic iron. The bismuth thus obtained is dried, 
and fused with an alkaline flux. A similar mode of treating the French ores 
has been carried out by M. Carnot. : 
Dr. Laspeyres, of Aix-la-Chapelle, has contributed to the ‘ Journal fur 
Praktische Chemie” a description of some artificial crystals of metallic anti- 
mony, accidentally obtained in slags at the Miinsterbusch Lead-Works, near 
Stolberg. Some antimonial residues and lead slags were smelted in a blast- 
furnace, with the view of obtaining a hard lead rich in antimony. The crystals 
appear at first sight to be regular cubes, resembling the well-known artificial 
galena, but are really rhombohedra of nearly go°, combined with the basal 
