Democratic Sentinel, Volume 19, Number 32, Rensselaer, Jasper County, 16 August 1895 — HOW IRON IS MINED. [ARTICLE]

HOW IRON IS MINED.

Processes That Hava Coma Into Ro. cant Use.J Back in tho hills of the Bald Eagle valley of Pennsylvania can be found the most productive ore mines that exist in any of the Northern states, says the Pittsburg Dispatch. The manufacturing in that section seemed to commence as sovn as the first settlement was made, and now there can be found some of the most interesting and historical facts concerning the early manufactnre of iron in its every stage of completion, from the time it leaves the mine as ore until it reaches its last finish as true steel. It was here in this valley that the charcoal blast furnace, once so popu lar, but now almost unheard of, made its initial appearance in 1865; but everything has undergone a change since that time, and now the only thing left to the once popular mode of manufacture of iron is one small wooden structure which is the charcoal blazing furnace, the place where the grandfather of the late Gov. Curtin made his first start in life as an ironmaster, In the place of these once famous furnaces there have been erected chill blast furnaces of a more modern kind, but the old mines are still as productive as they were a hundred years ago, and from all indications are likely to continue so. In ancient times it Was the custom in mining ore to dig straight down to perhaps a depth of 50 to 100 feet, and then strike out and take up the vein from the base of the pit; but this has been done away with entirely, and the only plan now carried into effect is to first remove the surface of useless gravel, and then to mine the entire contents, which plan makes mining practically as safe to man as almost any other work. Of course, the pew plan is a trifle more expensive, as the ore has to be gone over by men and boys, so that all the flint can be taken out. However, this slight expense is more than made up in the end, as mining by the modern methods can be carried on all winter, which formerly was impossible under the pit, or single vein system. Down into the depths of the mine nearest to the “washer” of a group of mines is run an incline of heavy plank at about an angle of 45 degrees, on which a double track is laid; at the top of this incline is the engine room and dumping house, while the empty car goes down on one side its own weight draws the loaded car up on the other side, like an endless chain, slacking up so the loaded car will have time to be dumped into the washing cars, which are run under the incline to receive the ore. From the mine the ore is taken to the “washers,” where it is thoroughly washed and the flint picked out; it is then ready for the market. All along the railroads near the mines are small loading stations where the ore is loaded onto the cars ready to be shipped to the furnaces. At many of the furnaces a high trestle work runs the cars right over the receiving tank, but in most cases the ore is raised to the tank by elevators, which are run similar to the cars on the incline. It is here in the large tank like structure that the ore, mixed with crushed coke is melted and made into pure iron, the cinder and refuse being skimmed off the surface while the iron is melting. The foreign substances which iron contains modify its essential properties. Carbon adds to its hardness, but destroys some of its qualities, and produces cast iron or steel according to the proportion it contains. Sulphur renders it fusible, difficult to weld, and brittle when heated or “hot short.” Phosphorus rendersit “cold short,” but may be present in the proportion of 2-1,000 to 3-1,000 without affecting injuriously its tenacity. Antimony, arsenic and copper have the same effect as sulphur, the last in a greater degree. The process of making cast iron depends much upon the description of fuel used; whether charcoal, coke, bituminous or anthracite coals. A larger yield from the same furnace, and a great economy in fuel, are effected by the use of a hot blast. The greater heat thus produced causes the iron to combine with a larger percentage of foreign substances. These substances and also a portion of foreign ingredients from the ore, such as earths of oxides of other metals, and sometimes sulphur and phosphorus, which are all injurious to its quality are separated by melting the iron in contact with air, and soft iron is thus rendered harder and stronger. Iron is improved in quality by judicious working, reheating it and hammering or rolling; other things being equal, the best is that which has been wrought the most.