OP ARTS AND SCIENCES. 201 



hedral oxide of iron. A mineral with a lime and soda base was also 

 found. The iron was most readily acted on by chemical agents, 

 where it was in contact with these minerals ; exposure of a surface 

 to the action of an acid not only brought them to view, but produced 

 cavities at the points where they existed ; showing degrees of porosity 

 influenced by their number. 



" The sp. gr. of the most compact portion was 6.708. Its color 

 was lighter gray than any sample of artificial ductile iron I have seen. 

 Repeated bending back upon itself did not separate one fragment, 

 but generally flaws appear and thin portions break when doubled 

 close. The presence of the minerals imbedded is felt, when we 

 file or saw the metal ; but when heated and hammered, these fuse 

 into slags, and the metal spreads and draws off", like the best irons, yet 

 showing the cavities and flaws where the simple minerals had existed. 



" Chemical Characters. — It dissolves with effervescence in diluted 

 hydrochloric acid, and if the acid and water are perfectly pure, the 

 evolved gas has no odor. 200 grains were dissolved in hydrochloric 

 acid, the hydrogen gas was passed through pure alcohol kept cool, and 

 was then allowed to bubble through an ammoniacal solution of nitrate 

 of silver. The alcohol had not acquired odor, nor was there any 

 coloration or change in the silver solution. The solution of iron was 

 turbid, but soon deposited suspended matter, which was light-gray 

 colored ; some heavy white sandy grains, and some dark, nearly black 

 particles, had fallen. After collecting and drying these substances, 



of its parts, and generally consists of perfectly pure and malleable iron, disturbed 

 in the arrangement of its crystalline particles by the interposition among them of 

 a compound of iron and carbon and of graphitic carbon, besides sulphides, phos- 

 phides, and arsenides of the alkaline metals. In the ductile iron, these bodies 

 have been nearly all removed by heat and mechanical operations, and new features 

 impressed upon the metal. By simply removing the interposed foreign matter, 

 by chemical means solely, crude iron is left malleable, and its particles then show 

 their sub-crystalline forms, but not as they exist in the pure iron of the more per- 

 fect meteoric masses. All manufactured iron presents them arranged in lines and 

 interlaced by the action of the hammer, or extended in bundles in the act of draw- 

 ing ; while the laminating mill breaks them down, shingling them over and felting 

 together their serrated edges, in striking analogy of effect to the operations of 

 textile manufacturing. The mechanical texture of a mass of iron cannot be 

 shown fully by the simple step of immersion as above given, but this is sufficient 

 to enable one to observe whether the crystals have arranged themselves as aggre- 

 gates, or been broken up and disturbed by violence, and often will serve to show> 

 the kind of mechanical action employed." 



VOL. III. 26 



