Abstract: A rotary hearth furnace has a mixing rabble arrangement that includes a first rabble disposed upstream a flow of material on the hearth and a second rabble disposed downstream a flow of material on the hearth. The first and second rabbles are disposed at an acute angle with respect to a center of rotation of the hearth in a manner so that a plane defined by a plow of the first rabble intersects a plane defined by a plow of the second rabble adjacent the leading edge or training edge of the plow of the second rabble. The rabbles cooperate to produce a counter-rolling action in the material as the material is advanced into contact with the rabbles by movement of the hearth relative to the rabbles.