Title Thirty years of labor, 1859-1889, in which the history of the attempts to form organizations of workingmen for the discussion of political, social and economic questions is traced. The National labor union of 1866, the Industrial brotherhood of 1874, and the order of the Knights of labor of America and the world. The chief and most important principles in the preamble of the Knights of labor discussed and explained, with views of the author on land, labor, and transportation. By T. V. Powderly.