IRON 



3057 



IRON 



graphical Society. The climate is healthful, 

 owing to the high altitude. Irkutsk is an im- 

 portant commercial point, for it is the central 

 trading station for China, Siberia and Russia. 

 Large quantities of silk, porcelain and furs are 

 exchanged there. The population in 1911 was 

 108,000, 5,000 being exiles. It was thought that 

 many of the latter would return to European 

 Russia after the amnesty which followed the 

 Russian revolution of 1917. 



IRON, i' urn, a metal which might well be 

 called the keystone of modern industry and 

 material civilization; if deprived of it, the 

 world would almost be reduced to the state 

 of our barbaric ancestors. We have only to 

 look about us to realize its importance. Our 

 homes are entirely or in part held together 

 by iron nails and screws; our doors are hung 

 on iron hinges and have iron latches and locks, 

 and we use iron stoves and iron cooking uten- 

 sils. Our clothing, too, is partly iron, for we 

 have nails in our shoes. The trains and street 

 cars and automobiles that take people to work 

 and the tracks upon which the first two run 

 are largely of steel (which is one form of iron), 

 and our business buildings are often built with 

 steel frames or of concrete reinforced with 

 steel. 



Industry is dependent most of all on this ex- 

 ceedingly valuable metal, for practically all 

 machines and tools in factories or on farms, 

 from tack hammers to giant cranes, are com- 

 posed of it, and iron steamers and iron engines 

 move their products. Besides serving us in all 

 these ways and countless others which sharp 

 eyes will discover, iron because of its magnetic 

 properties makes possible the telegraph 'and 

 telephone. Last of all, it is a part of our own 

 bodies and is present in plants, giving to the 

 first their red blood and to the second their 

 green leaves. 



Imagine how helpless we should be without 

 saws and knives and with hammers and hatch- 

 ets of stone! The commencement of the Iron 

 Age marked a great step in mankind's history. 

 We do not know just when this was; of course 

 it was at a different date in different parts of 

 the world, and to some races it has not yet 

 come. There is a piece of iron in the British 

 Museum in London which is thought to have 

 been made six thousand years ago. It is Egyp- 

 tian, but probably the Assyrians were the first 

 to become skilled workers in the metal. From 

 them the neighboring nations learned of it and 

 we read of iron in the very oldest books of 

 the Bible. The ancient Britons appear to have 

 discovered for themselves the art of smelting, 

 but may have been taught it by the Phoeni- 

 cians. It must have been by accident that iron 

 became known, for it is very seldom found in 

 the pure state, and to separate it from its ore 

 requires intense heat. 



Iron Ore. There is iron almost everywhere. 

 It is part of the sun and the planets, and is the 

 commonest element in the meteorites that fall 

 from the sky. On the earth it is present in all 

 good soils, but of course to mine it does not 

 pay, except where there are large quantities of 

 it. Many deposits of iron ore which are at 

 present untouched will become valuable when 

 the price of the metal rises, when new inven- 

 tions make mining cheaper, or when improved 

 transportation brings them into closer touch 

 with the centers of manufacture. 



The ore is usually hard rock, which must be 

 blasted and mined underground, but in the 

 great Mesaba range of Minnesota it is so soft 

 and so near the surface that it is taken out 

 with steam shovels running on railroad tracks. 

 These shovels can load a fifty-ton car in three 

 minutes. This accessibility makes the Mesaba 

 the most valuable iron region in the world. 



How Iron Is Manufactured 



Because it takes two tons of fuel to smelt one 

 ton of iron ore it is economical to carry the 

 ore to the coal regions. Thus in the United 

 States the great centers of iron manufacture 

 are in and around the coal fields of Western 

 Pennsylvania, which is also nearer to the points 

 where the finished steel and iron are wanted. 

 In the Birmingham district of Alabama both 

 coal and iron, and a third important element, 

 limestone^ are found; this unusual combination 

 makes smelting profitable, though the ores con- 

 tain less iron than those usually mined. The 

 192 



steam-shovel-mined ore from the great Minne- 

 sota mines is taken by railroad to Lake Su- 

 perior and fed into ore-carrying boats through 

 chutes from a high dock. At the other end 

 of the Great Lakes it is unloaded mechanically 

 and left in huge piles outside the works. Be- 

 cause the lakes are frozen in winter a year's 

 supply has to be brought each summer. Re- 

 cently a ten-million-dollar plant was erected 

 at Duluth by the United States Steel Corpora- 

 tion, and this establishment will consume great 

 quantities of raw material. 



