Technological advances were important to Second Industrial Revolution, period of rapid growth in U.S. manufacturing in late 1800sBessemer process, invented mid-1850s, allowed steel to be produced quickly and cheaply.Helped increase steel production from 77,000 tons in 1870 to more than 1 million tons in 1879As steel dropped in price, so did the cost of building railroads, generating a boom in railroad construction.Growth of railroads elped the country expand and prosper
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