<P> Landes (2003) stresses the importance of new technologies, especially, the internal combustion engine and petroleum, new materials and substances, including alloys and chemicals, electricity and communication technologies (such as the telegraph, telephone and radio). </P> <P> Vaclav Smil called the period 1867--1914 "The Age of Synergy" during which most of the great innovations were developed . Unlike the First Industrial Revolution, the inventions and innovations were engineering and science - based . </P> <P> A synergy between iron and steel, railroads and coal developed at the beginning of the Second Industrial Revolution . Railroads allowed cheap transportation of materials and products, which in turn led to cheap rails to build more roads . Railroads also benefited from cheap coal for their steam locomotives . This synergy led to the laying of 75,000 miles of track in the U.S. in the 1880s, the largest amount anywhere in world history . </P> <P> The hot blast technique, in which the hot flue gas from a blast furnace is used to preheat combustion air blown into a blast furnace, was invented and patented by James Beaumont Neilson in 1828 at Wilsontown Ironworks in Scotland . Hot blast was the single most important advance in fuel efficiency of the blast furnace as it greatly reduced the fuel consumption for making pig iron, and was one of the most important technologies developed during the Industrial Revolution . Falling costs for producing wrought iron coincided with the emergence of the railway in the 1830s . </P>

What effects did the second industrial revolution have upon western society