320 Notice of Steel Mine and Iron Works. 



es through several shades of brown, hito a brownish or iron black 

 color, — losing, at the same time, its lustre, and becoming opake. 

 Specimens which have been exposed a still longer period, sometimes 

 lose their coherence, and crumble down to a powder. 



So numerous and accurate are the analyses which chemists have 

 made of this species, and so uniform have been their results, that 

 a regular analysis of specimens from this place is not requisite : it will 

 be sufficient to remark, that the steel ore always consists of the oxide of 

 iron at the lowest state of oxidation, and carbonic acid, in the propor- 

 tion of, from 57 to 60 per cent, of the former, and 34 to 36 per cent, 

 of the latter; together with a proportion of manganese from 0.5 to 

 1.5 per cent., and magnesia and lime, in about the same proportion: 

 these last are, however, less constant in their proportions than the man- 

 ganese. In those cases where the magnesia exists in larger propor- 

 tions than is above mentioned, it has been found to offer some ob- 

 stacles to the reduction of the ore by the economical method of the 

 Catalan forge : this, of late, however, is said to have been obviated, 

 simply by exposing the ore in heaps, for a year or two, to the weath- 

 er ; during which time, it becomes sufficiently decomposed to part 

 with its excess of magnesia.* 



I can find no precise statement of the usual yield of iron or steel 

 from the Sparry Iron. The chemist, however, knows perfectly well 

 the proportion of iron it contains. Taking the lowest proportion of 

 protoxide of iron, analysis has discovered in it, from the known com- 

 position of protoxide of iron, we have 44 per cent, of metallic iron in 

 the Sparry iron ore. But as we know that the reduction of the ores 

 of iron in the large way, is attended with a loss, varying from one 

 third to one half of the metal, it would not be far from truth to 

 place the yield of this ore at 25 or 30 per cent. The quantity of 

 charcoal required to obtain 100 pounds of iron or steel, is stated to 

 be, from 500 to 540. 



The situation of this deposit of ore, as respects the vicinity of wa- 

 ter and wood, is such as, in a very remarkable manner, to facilitate 

 its being wrought. And in the first place, as regards a stream of 

 water adapted to the construction of those hydraulic machines which 



^ The ren)oval of the magnesia under these circumstances may be attributed to 

 the natural oxygenalion of the sulphur contained in the Pyrites disseminated through 

 the ore, — thus giving rise to sulphuric acid, which, combining with the magnesia, 

 forms the well known compound, called Epsom salts; which is conveyed away from 

 the ore by the rains to which it is exposed, as fast as its formation takes place. 



