It was only a step for the steam engine into a new field of labour when General Bentham introduced his system of wood-sawing machinery in 1800; and from sawing wood to sawing stone was only one more step. We find that taken in 1803 in Pennsylvania, when Oliver Evans of Philadelphia drove with a high-pressure steam engine, “twelve saws in heavy frames, sawing at the rate of one hundred feet of marble in twelve hours.” How long would it have taken hand sawyers of marble at ancient Paros and Naxos to have done the same? _Stone-cutting_ machines of other forms than sawing then followed. It was desired to divide large blocks generally at the quarries to facilitate transportation. Machines for this purpose are called stone-channelling machines. They consist of a gang of chisels bound together and set on a framework which travels on a track adjacent to the stone to be cut, and so arranged that the cutters may be set to the stone at desired angles, moved automatically forward and back in the grooves they are cutting, be fed in or out, raised or lowered, detached, and otherwise manipulated in the operation. Other stone-cutting machines had for their objects the cutting and moulding the edges of tables, mantels and slabs; and the cutting of circular and other curved work. In the later style of machine the cutter fixed on the end of a spindle is guided in the desired directions on the surface of the stone by a pointer, which, attached to the cutter spindle, moves in the grooves of a pattern also connected to the rotating support carrying the cutter. Other forms of most ingenious stone-dressing and carving machines have been devised for cutting mouldings, and ornamental figures and devices, in accordance with a model or pattern fixed to the under side of the table which carries the stone or marble to be dressed; and in which, by means of a guide moving in the pattern, the diamond cutter or cutters, carried in a circular frame above the work and adjusted to its surface, are moved in the varying directions determined by the pattern. A stream of water is directed on the stone to clear it of the dust during the operations. The carving of stone by machinery is now a sister branch of wood carving. Monuments, ornamentation, and intricate forms of figures and characters are wrought with great accuracy by cutting and dressing tools guided by the patterns, or directed by the hand of the operator. For the dressing of the faces of grindstones, special forms of cutting machines have been devised.