1907. The wheel-platform (fig. 512.) is a flat surface of boards, generally five or six feet square, elevated by a frame with wheels: it can thus be moved along lawns or walks, and is used chiefly in clipping lofty hedges. A variety of this, used in some places, has folding steps or boards on two sides, supported by brackets, by which three men at different heights, and one on the ground, can proceed with dressing the whole side of a hedge at once. Such a machine is used in shearing the magnificent hornbeam hedges in the imperial gardens at Schonbrunn, and those of spruce fir at Petrowsky, near Moscow.