POPULATION CHANGE AND TECHNOLOGICAL INNOVATION

If the demise of the lead industry of Derbyshire seemed imminent in the mid-sixteenth century, in the lead mining districts of the Somerset Mendips 200 miles to the south, the future seemed rosy. Here, the constraints imposed on the industry by bole smelting methods had been removed. At some point in the 1540s, lead ore started to be smelted according to a new method: a foot-powered bellows heated burning charcoal, under which lead ore was placed. This ‘footblast’ was soon superseded by a further development upon the principle: the ore hearth smelting mill. Smelting houses were built alongside fast-running streams, which provided the motive force for a water wheel. This drove powerful bellows, forcing air into a furnace containing lead ore, which was then smelted at high temperatures. Unlike the bole, the ore hearth mill did not depend upon the vagaries of the weather, could produce ore throughout the year and was capable of smelting a low grade of ore.

The first such mill was introduced into Derbyshire in 1552, but met with little success. Around 1569, a second ore hearth mill was established at Beauchief by William Humphrey, who had acquired the monopoly on its operation in 1564. The success of Humphrey's mill encouraged imitators amongst the local brenners, gentry and nobility. Running legal and political battles ensued over the subsequent decade, but by the late 1570s Humphrey was forced to recognize that his attempt to monopolize the ore hearth mill had failed.