178 Miracles Ahead! 



nesium alloys to be utilized in postwar automobile engines, 

 making them lighter and more efficient. These alloys also will 

 be useful in home construction, household appliances and 

 equipment, and scores of other applications. 



Only 6,000,000 pounds of magnesium were produced in 

 the United States in 1939, while at the end of 1942 produc- 

 tion was at the rate of 260,000,000 pounds. It was stepped 

 up during 1943 to 627,500,000 pounds. 



"Tailor-Made" Steel 



We need iron in our blood, and iron and steel are the 

 "lifeblood" of modern industry. With the exception of alu- 

 minum, iron is the most common metal in the earth's crust. 

 It is found combined with oxygen in such ores as hematite 

 (most important iron ore in the United States), magnetite, 

 and limonite. Iron is obtained from the oxide by heating it 

 with carbon and removing certain impurities. Steel is merely a 

 kind of iron which is hardened by burning out the carbon 

 and other impurities and then adding just the correct amount 

 of carbon. Harder steel can be made by heating and then cool- 

 ing it suddenly by "quenching" in water or oil. Softer steel 

 can be produced by heating it and allowing it to cool 

 slowly. 



Special kinds of "tailor-made" steel can be produced by 

 adding small amounts of other metals. These steel alloys make 

 the armor plate for ships and tanks, and the guns and other 

 equipment that give our armed forces their tremendous strik- 

 ing power. 



Pinkish-gray manganese makes a tough manganese steel 

 which is used in railroad switches, dippers of power shovels, 

 rock crushers, and other equipment that must stand hard 

 wear. Manganese also is vital in the production of all kinds 

 of steel. Small amounts of this metal are added to steel to 



