Abstract: A mining machine of the type wherein the rotary mining head comprises at least one rotatable support carrying a plurality of cutter drums. The support is rotatably driven through a gear box including gearing connected to the support by a plurality of drive shafts, thereby providing the mining head with substantially increased power and torque, for the employed diameter of drive shaft, while also providing other described advantages. Each of the drive shafts is connected to the gearing through a clutch whereby the load is divided between the drive shafts and the shafts are automatically disconnected from the gearing in the event that the mining head encounters high resistance to its driven rotation.