The name of _freestone_ has been given to this kind of rock, from its capability of being broken or hewn, with nearly equal facility, in any direction. Hence, as well as from its great durability, it is peculiarly esteemed for buildings. It is also formed into cisterns and troughs of various kinds; into pillars for supporting corn ricks; into _rolling stones_; and into _grinding stones_ for cutlers, edge─tool makers, and workers in polished steel. _Paviors’ flags_, or the stones used for the paving of footpaths, yards, kitchens, and out─houses, are generally flat pieces of freestone. _Scythestones_, or stones for the sharpening of scythes upon, are made of freestone. Considerable numbers of these are wrought in Derbyshire; and the dexterity that is displayed in cleaving and forming them is somewhat remarkable. The workmen use sharp─pointed picks, several very small wedges, and a hammer. A proper block of stone being selected, two or three of these small wedges are set in a row, by gentle blows of the hammer. These blows are successively repeated till the stone splits. The wedges are then set in a straight line into the face of the piece split off, and the stone is cleft again in that direction. In this manner the sub─divisions are continued, until a piece remains of size to make two scythestones, each an inch and a half square, and about twelve inches long. This the workman holds in his left hand, nearly upright; with the point of his pick he traces a deep nick down the middle of first one side and then the other; and then by a slight blow of his pick he separates it, into two, so dexterously, that not more than three or four in a hundred are broken in the cleaving. Such stones as are intended for round rubbers, are first reduced into an octagonal shape by the point of the pick, and then handed over to women and boys, who grind or rub them in a notch formed in a hard stone, until they are of the requisite shape. The square ones are finished by being ground on a flat stone. * * * * * Other rocks, belonging to what is called the floetz, or flat formation, have been already mentioned, under the heads of _lime─stone_ (140), _gypsum_ (192), _rock salt_ (202), _chalk_ (141), and _coal_ (217). III. ALLUVIAL DEPOSITIONS. 269. _These are described to comprehend all such substances as have been formed from previously existing rocks, of which the materials have been worn down, by long exposure to the agency of water and air, and afterwards deposited in nearly horizontal beds on the surface of the land._ Alluvial deposits have been formed, and are still forming in every quarter of the globe. They occur both in mountainous regions and in flat countries, filling up the valleys or hollows in the one; and often forming vast and extended plains in the other. They consist of _peat_, _sand_, _gravel_, _loam_, _clay_, and other substances. IV. VOLCANIC ROCKS.