Cook County inmates returned to the Mercer County Jail today. A busload of ten prisoners checked in this afternoon says Mercer County Sheriff Bill Glancey. He anticipates more in the coming days and weeks. Cook County had stopped sending inmates to Mercer County in late January partly due to the harsh winter, according to Glancey. The county receives $50 per day per Cook County prisoner and $65 per day per U.S. Marshals Service prisoner housed at the jail.