>Steam power wasn't feasible until the Bessemer process and rolled sheet steel made the creation of pressure vessels a reliable and repeatable process. Also pr

>Steam power wasn't feasible until the Bessemer process and rolled sheet steel made the creation of pressure vessels a reliable and repeatable process. Also precision boring to produce tight-fitting cylinders. James Watt spent nearly a decade trying to build a viable steam engine, but only succeeded after John Wilkinson invented a machine to bore cannon barrels in 1774. It turns out that making a hole that is straight, deep and round is fiendishly difficult without specialist equipment and expertise.