Changes in the skill differential are often used by economic historians to proxy changes in income inequality. According to Jeffrey Williamson and Peter Lindert, American skill differentials rose sharply between 1820 and 1860, which they interpret as increasing income inequality. Using a large,...

During the nineteenth century, the US manufacturing sector shifted away from the "hand labor" mode of production, characteristic of artisan shops, to the "machine labor" of the factory. This was the focus of an extremely detailed but extraordinarily complex study by the Commissioner of Labor...