<P> In the 1830s, French political thinker and historian Alexis de Tocqueville identified one of the key characteristics of America that would later make it so amenable to the development of mass production: the homogeneous consumer base . De Tocqueville wrote in his Democracy in America (1835) that "The absence in the United States of those vast accumulations of wealth which favor the expenditures of large sums on articles of mere luxury...impact to the productions of American industry a character distinct from that of other countries' industries . (Production is geared toward) articles suited to the wants of the whole people". </P> <P> Mass production improved productivity, which was a contributing factor to economic growth and the decline in work week hours, alongside other factors such as transportation infrastructures (canals, railroads and highways) and agricultural mechanization . These factors caused the typical work week to decline from 70 hours in the early 19th century to 60 hours late in the century, then to 50 hours in the early 20th century and finally to 40 hours in the mid-1930s . </P> <P> Mass production permitted great increases in total production . Using a European crafts system into the late 19th century it was difficult to meet demand for products such as sewing machines and animal powered mechanical harvesters . By the late 1920s many previously scarce goods were in good supply . One economist has argued that this constituted "overproduction" and contributed to high unemployment during the Great Depression . Say's law denies the possibility of general overproduction and for this reason classical economists deny that it had any role in the Great Depression . </P> <P> Mass production allowed the evolution of consumerism by lowering the unit cost of many goods used . </P>

Who perfected the mass production of supply ships