_It is very common in several parts of England, generally among chalk, arranged in a kind of strata or beds, and in pieces that are for the most part either rounded or tubercular._ The property which flint possesses of yielding sparks, when struck against steel, has rendered it an article of indispensable utility in the system of modern warfare. To this substance the sportsman also is indebted for a means of obtaining his game. The art of cutting, or rather of breaking, this stone into gun─flints is of modern date, and was for a long time kept secret. The most absurd and contradictory accounts have been given of it by various writers; and it is only of late that the true mode has been rendered public. It consists in striking the stone repeatedly with a kind of mallet, and bringing off at each stroke a splinter which is sharp at one end and thick at the other. These splinters are afterwards shaped, by placing them upon a sharp iron instrument, and then giving them repeatedly small blows with a mallet. During the whole operation the workman holds the stone in his hand, or merely supports it on his knee: and the operation is so simple, that a good workman has no difficulty in making 1500 flints in a day. The manufacture of gun─flints is chiefly confined to England, and two or three departments in France. In Prussia an attempt was once made to substitute a kind of earthenware or porcelain for flint; and such was, for some time, used by the Prussian soldiers. All the kinds of flint are not equally adapted for guns: the best are the yellowish grey; the dark smoke and ash─grey varieties are also used, but they are neither so easy to be split, nor do they afford such thin fragments as the other; and, owing to their greater hardness, they wear the lock sooner. Flint is employed in the manufacture of porcelain and glass. For this purpose it is heated red hot, and, in that state, is thrown into cold water. It is then of a white colour, and capable, without difficulty, of being reduced to powder, either in a mortar or by a mill. After this powder has been passed through fine sieves, some aqua fortis is poured upon it, to dissolve any particles of iron which it may have acquired in the grinding. The powder is then several times washed in hot water, and afterwards dried for use. The glass that is manufactured from this substance is perfectly transparent and faultless.