Rensselaer Republican, Volume 26, Number 24, Rensselaer, Jasper County, 8 February 1894 — A BAR OF IRON. [ARTICLE]

A BAR OF IRON.

Preliminary Processes That Are Necessary to Its Production. Harpers Magazine. Iron-making is a kin of cookery on a huge scale. The earthy impurities must be “roasted” or melted out from iron ore; necessary carbon must then be properly mixed in from the fuel, or the unnecessary carbon burned out. This is of manufacture. A wrought-iron bar or plate is always obtained from a puddle ball, an aggregation of grains of iron in a pasty, .semi-fused condition, interspersed with a greatsror less amount of cinder or slag. Under the powerful action of the rolls the grains are welded together, and a large part of the cinder is squeezed out, but enough remains interposed between the iron granules to prevent them from welding thoroughly and forming a homogeneous mass. The welded lumps elongate under the process of rolling, and the resulting bar resembles a buuch of iron fibres or sinews with minute particles of slag interpspersed here and there. Such iron varies.in resistance according to whether the power is applied with or against the fibres. Steel is the result of a fusing process. It mav be crucible, Bessemer, or open-hearth steel, but iu all cases it ha« been cast from a thoroughly melted and fluid state into an ingot mould, whore it solidifies and is ready for subsequent treatment, such as hammering or rolling. The slag being lighter than the steel, it rises on top of the melted bath, and does not mingle with the metal, which remains clehn and unobstructed, and, after being cast in the mould, cools into a crystalline homogeneous mass in which no amount of rolling ' can develop a fibre. Thus steel possesses a structure more regular and compact than wrought iron. Its resistance to strains and stresses is more equal in all directions, and its adaptability to structural use is vastly increased.