For much of mining history, miners struggled to earn a living wage because work was unsteady. Before the 1930s, intermittent work was the main problem, and from 1890 to 1930 the nation’s coal mines operated only about two-thirds of full time. Strikes and lockouts contributed to this idleness through recurring conflicts between coal operators and the United Mine Workers of America, but the chief cause was weak market demand for coal. By 1910, the industry had expanded beyond what the nation could consume, and operators without orders or enough railroad cars were forced to shut down periodically, costing miners wages. Southern West Virginia’s miners were somewhat more fortunate because union activity was restricted there, leading to fewer stoppages from strikes and lockouts, and they averaged 231 working days during this period. Even so, demand problems and car shortages remained. During World War I, miners worked nearly full time because coal was in great demand, but in the 1920s and 1930s overexpansion worsened and miners were idle nearly as much as they worked; in 1921, West Virginia’s miners averaged only 149 working days. A new threat to miners’ livelihoods came with mechanization. Cutting machines first appeared in the 1890s, but loading machines in the 1930s and 1940s and continuous mining in the 1950s and 1960s brought the full force of mechanization, costing thousands of miners their jobs. In southern West Virginia, this unemployment was felt especially sharply. Black coal miners, who made up nearly one-third of the mining labor force, were affected first, as loading machines such as the Joy loader rapidly displaced them in the 1930s and 1940s. Many black miners and their families left the region, and by 1980 the number of black miners in the state had fallen by more than 90 percent. After state mining employment peaked at 125,000 in 1947, it dropped to 65,000 by 1954 and to 49,000 in 1960. Widespread unemployment devastated mining communities in southern West Virginia as coal companies abandoned their towns and thousands of miners left the coalfields for manufacturing jobs in Ohio or Michigan. After organizing nearly all of the nation’s miners in 1933, the miners’ union agreed to support mechanization in exchange for benefits from greater productivity, including higher wages, a seniority system, and eventually a welfare and retirement fund. John L. Lewis, president of the United Mine Workers of America, recognized that mechanization would eliminate thousands of mining jobs, but regarded it as the only solution to the industry’s chronic overexpansion.