214 
Iron 
of various proportions of manganese and iron fused toge- 
ther, But the opinions of an experienced iron master and 
a good blacksmith, should be taken upon the specimens 
produced. 
Arsenic, is best detected by roasting the pulverized ore ; 
but Bergman could detect none in the cold-short iron of 
Grange : but he says that its presence, deprives iron of 
its magnetism, and renders it both red-short, and cold- 
short. Muriatic acid will take up the iron and leave the : 
arsenic. Aqua regia will take up both, but water will 
throw down the arsenic. 
Zinc is sometimes found in iron, but seldom. The 
cold-short property is not attributable to this metal. The 
blue colour of the bright flame, and the white sublimate 
discover it. But it is not found in cold-short iron. 
With respect to plumbago, Bergman was not aware, 
that a superabundant quantity of charcoal would form it : 
nor did he then know, I believe, that black lead or plum- 
bago was a very carburetted iron, in which the iron was 
in small proportion. 
With respect to the acid of vitriol, modem knowledge 
will acquit it of forming any component part of iron, or 
of being instrumental in any of its faults. 
It is singular that in Bergman’s Experiments, cold-short 
iron dissolved in acids, and precipitated by the prussiat 
of potash into Prussian blue, continued cold-short on 
being again reduced into metallic iron. 
Bergman also attributed the quality of cold-short iron 
to siderite or phosphat of iron ; but I agree with Mr. 
Mushet that the violent heats of a furnace and refining, are 
sufficient to decompose this substance. 
Nickel has been found in iron, but I know not of any 
bad effect from it. Nickel precipitated with iron, and the 
latter reduced to a red or peroxide by hy per- oxv muri ate 
of lime, die nickel may be separated by pure ammonia. 
