466 FORTlA’s TRAVELS IN SWEDEN .

The officers are a president, a matter of the mines, two jurors, a fifcal, a matter ofthe engines, eight Jligare y a comptroller for dividing the ore, a number of “book-keepers,and at the weighing engine an infpedor on account of the crown. The council of themine fits twice a week: as often as any occurrence takes place of any importance regard-ing the fociety, it affembles and givps its advice.

Here a variety of ores, rock, and other ftones are found in abundance, that is to fay,precipitate of copper, yellow copper ore, fteel grained, fcoriae grained, white copper ore,yelloyy, hepatic, grey, black, very much impregnated with iron, yellow in oftaedra, en-crufted with mica; iron ore of a blackifh calf, which anfwers the magnet, very rare ,and oritaedral encrufted with mica, likewife attra&ed by the magnet, cryftallized gyp-fum, rhomboidal and prifmatic, martial pyrites, fometimes in a cryftallized ftate; mineralpitch, rather rare, fluoric cryftallized gypfutn, and white ftriated calcareous fpar, gra-nulated calcareous ftone, rock garnets, garnets cryftallized in decaedra, fometimes aslarge as a man’s head; (Mr. Gahn has one of an enormous fize ;) a rock of fibrous ftri-ated and ftarry fchoerle, potter’s ftone, granulated and folid quartz, undtuous and dry ;amianthus, galena fraught with filver in large cubes and fcaly, fcaiy blend, blue, green,and white native vitriol, the latter very rare; zeolites very friable, and of a brick colour ;fometimes among the fcorise you meet with curious matters among other cryftals of thefame form as the bluilh cellulary hematites.

Vitriol manufactory. In 1775, by private contract, a privilege was granted to threeperfons to make vitriol; the water from the mine is received in a refervoir,. and thencecondudted by-a canal to fix compartments, made on a very high wooden fcaffold, onehundred and twenty-eight feet long ; thefe canals have a number of holes on each fideto admit the water to drop over faggots of three feet breadth, fome lying and otherseredt, made of birch for want of other wood ; fixty-fix cocks let out the water into thefix compartments of the canal, which is a&out two feet broad from one extremity tothe other, perhaps an inch more at the entrance of the firft compartment ; this flightincreafe of breadth, however, we conceive, has been accidental, although the fize of thecompartments might be lefs by degrees fince the volume of water decreafes. The wateris then let into the firft compartment, whence it falls into another refervoir, through thechinks; it is carried back into the fecond, whence it drops again into the third refer-voir, and fo on to the fixth, when it is plain it will depofit molt of vitriolic matter, thequantity encreafing at every frefh exudation. The fpecific gravity of the water being1280, on coming from the mine is reduced after the graduation to 1250, or at mod1 260. In winter the works are fufpended. After this operation it is p'ut into leadenboilers with iron, to precipitate the copper, and faturate the acidity of the vitriol, wherethe water is evaporated for the fpace of twelve or thirteen hours, thence it is conveyedinto bafons to clarify, in which it depofits its fediment: to prevent the too fuddencooling of the matter, thefe bafons are made of wood coated with clay, and are coveredwith planks in thefe it remains from fix to twelve or twenty-four hours, according tothe gravity of the water; from thefe bafons it runs by means of fpouts into others to cryf-tallize, wherein it is fuffered to remain fourteen days, at the expiration of which the vi-triol remains at the bottom, on the fides, and adhering to flicks placed in the bafons; ifany fediment yet remains it is heated anew ; the cryftals are laid on an inclined plainfor the water to efcape: the lye or firft matter which is not cryftallized is poured intoa well apart, whence it is taken to be heated again with frefh lye. In order to dry thecryftals they are laid on fhelves of four ftories, and in two or three days, according to thefeafon, it is effected; the quantity of vitriol annually made is eight hundred fchip-