A previous post outlined a number of major inventions (or macro-inventions) of the eighteenth century that were basis for the inventions of the nineteenth century that propelled productivity growth. These innovations, according to Robert Allen, would not have taken place in Britain in the absence of cheap coal deposits. Another unique factor driving the innovations was Britain’s expensive labour. Labour was expensive in Britain, and economic historians have traced the origins of the high wages back to the Black Death plague (in the 14th century) that reduced the working age population significantly. Moreover, Britain’s commercial success in international economy played a role in the growth of wages.