[45] "The Growth of Labor Organizations in the United States, 1897-1914," in _Quarterly Journal of Economics_, Aug., 1916, p. 780. [46] "The Extent of Trade Unionism," in _Annals of American Academy of Political Science_, Vol. 69, p. 118. [47] _Ibid._ [48] "The Extent of Trade Unionism," in _Annals of American Academy of Political Science_, Vol. 69, p. 118. [49] The "federal labor unions" (mixed unions) and the directly affiliated local trade unions (in trades in which a national union does not yet exist) are forms of organization which the Federation designed for bringing in the more miscellaneous classes of labor. The membership in these has seldom reached over 100,000. [50] A small but immensely rich area in Eastern Pennsylvania where the only anthracite coal deposits in the United States are found. [51] At a conference at Columbus, Ohio, in January, 1886, coal operators from Western Pennsylvania, Ohio, Indiana, and Illinois met the organized miners and drew up an agreement covering the wages which were to prevail throughout the central competitive field from May 1, 1886, to April 30, 1887. The scale established would seem to have been dictated by the wish to give the markets of the central competitive field to the Ohio operators. Ohio was favored in the scale established by this first Interstate conference probably because more than half of the operators present came from that State, and because the chief strength of the miners' union also lay in that State. To prevent friction over the interpretation of the Interstate agreement, a board of arbitration and conciliation was established. This board consisted of five miners and five operators chosen at large, and one miner and operator more from each of the States of this field. Such a board of arbitration and conciliation was provided for in all of the Interstate agreements of the period of the eighties. This system of Interstate agreement, in spite of the cut-throat competition raging between operators, was maintained for Pennsylvania and Ohio practically until 1890, Illinois having been lost in 1887, and Indiana in 1888. It formed the real predecessor of the system established in 1898 and in vogue thereafter. [52] See above, 136. [53] The run-of-mine system means payment by weight of the coal as brought out of the mine including minute pieces and impurities. [54] The check-off system refers to collection of union dues. It means that the employer agrees to deduct from the wage of each miner the amount of his union dues, thus constituting himself the union's financial agent. [55] In that district the check-off was granted in 1902. [56] Hitchman Coal and Coke Company _v._ Mitchell, 245 U.S. 232. [57] See below, 175-177.