The Knights of Labor, based on the premise that workers of all types should be enrolled in “one big union,” had boomed from 28,100 members in 1880 to 729,000 six years later, but then fell back to 100,000 in 1890 and collapsed in 1894 in the face of internal conflicts between the skilled and unskilled, as well as between blacks and whites. Its leading role was soon taken over by the American Federation of Labor, along with a series of unions organized along craft and industrial lines—mine workers (founded in 1890), electrical workers (1891), longshoremen
