The use of a pair of conical drums in reversed position, and connected by a band, as shown in the cut, has been known for several years to a few, but yet are not extensively known, and but a few of them have been seen in operation in this country. It will be seen that if the band be removed laterally, either to the right or left, the relative motion of drums will be materially varied. These drums being arranged to constitute a connection of motion between the driving power and driven machine, may be made to render the motion of the latter either regular or irregular at the option of the operator. If the band connecting the drums, is governed by a shifting lever connected with a governor, it may be so adjusted as to keep the motion of the machine regular, although the driving power should be irregular in its motion, as is the case with a wind-wheel. But if the operator is engaged, requires a move rapid motion at one time than at another, he can accommodate himself by shifting the position of the cone-band, to the right or left, as occasion may require. This is very convenient for turners, whose business requires at some times a rapid speed of the mandrill, and at other times a slow or gentle motion. These drums, as represented, must be swelled in the centre, that the band may be kept uniformly straight.