"There were eruptions against the convict labor system in the South, in which prisoners were leased in slave labor to corporations, used thus to depress the general level of wages and also to break strikes. In the year 1891, miners of the Tennessee Coal Mine Company were asked to sign an "iron-clad contract": pledging no strikes, agreeing to get paid in scrip, and giving up the right to check the weight of the coal they mined (they were paid by the weight). They refused to sign and were evicted from their houses. Convicts were brought in to replace them."