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QUARTS FAMILY. in great abundance in beds, also imbedded in angulai' and tuberose-shaped masses, and in various extraneous shapes : and in amygdaloid it forms one of the consti tuent parts of agate, or occurs in veins. In alluvial country, it appears in the form of rolled masses, or gravel, and sometimes as coarse sand. 2. The imbedded masses of flint are frequently hollow, and the walls of the cavities are lined with crystals of quartz, and sometimes with crystals crf sulphur. 3. The beds of flint contained in chalk have been de posited in the same manner as other beds. The imbedded tuberose, arid Other shaped masses, according to Werner, have been formed by infiltration : he conjectures, that during the deposition of chalk, air was evolved, which, in endeavouring to escape, formed irregular cavities, that were afterwards filled up, by infiltration, with flint *. 4. It is often covered with a whitish crust, which is usually produced by weathering; but in other instances, appears to be an original formation. Geographic Situation. ' Europe.—In Scotland it occurs imbedded in floetz limestone in the island of Mull, and near Kirkcaldy in Pifeshire; and in veins and agates in primitive, transition, and floetz rocks in various parts of the country. In Eng land, it abounds in the form of gravel, also contained in chalk, in floetz limestone, and in veins that traverse both transition and floetz rocks. In Ireland it occurs in considerable quantity in floetz limestone. On * This ingenious idea of Werner may not be altogether correct, as fact* afterwards to be stated, render it probable that tuberose Mint is of cotemp 0 - raneous formation with the chalk.