Most slaves had been engaged in plantation agriculture and were destined to continue in some kind of farm work. Sumner and Stevens led the fight in Congress to provide each of them with forty acres and a mule, and this would have provided the basis for their developing into an independent class of farmers. However, they were doomed to remain a subservient mass of peasants. The prewar slave plantation was replaced by sharecropping, tenant farming, and the convict lease system. In some cases the ex-slave was provided with land, tools, and seed by plantation owner who, in turn, was to get a share of the crop at the end of the season. His share was always so large that the cropper remained permanently in his debt. Similarly, tenant farmers paid rent for their land and were extended loans by the store keeper for their provisions. Interest rates ran so high that they too remained in permanent bondage. Finally, some plantation owners leased convicts from the state and worked them in chain gangs which most closely resembled the prewar slave system. In every case, the result was that black farm laborers remained members of a permanent peasant class. The other hope for the advancement of the ex-slave was through the development of industrial skills. At this time the American labor movement was emerging and was striving to protect and elevate the status of industrial workers. If the ex-slave had been integrated into this movement, it would have helped many of them to achieve economic security. At the same time, it would have strengthened the labor movement itself. However, white workers usually saw blacks as job competitors rather than as part of a mass labor alliance. In 1866 the National Labor Union decided to organize black workers within its ranks, but by 1869 it was urging colored delegates to its convention to form their own separate organization. This resulted in the creation of the National Negro Labor Convention. This split between black and white workers tended to push blacks into political action while whites put all their efforts into economic advancement. The Knights of Labor was formed in 1869, and it did seriously try to organize blacks and whites. In the North it operated mixed locals, and in the South it had separate black and white organizations. It employed both black and white organizers. In 1886 its total membership was estimated at 700,000 of which 60,000 were black. The following year its total membership had shrunk to 500,000, but its black membership had increased to 90,000. The early labor movement which strove to organize the mass of industrial workers was soon replaced by skilled trade unions which aimed at the organization of a labor elite.