of the Pyrites. 337 



The method of working for fulphur at Dylta in 

 the Province of Nericia in Sweden, we mall next 

 defcribe. This is is one of the greater! works for 

 fulphur in the whole kingdom ; and here they alfo 

 boil for vitriol and alum. The matters, from 

 which all thefe things are drawn and prepared, are 

 a yellow- greenifli, dark-mining, ponderous pyrites^ 

 not breaking there in the high-land, nor at great 

 depths, but beneath the under-turf earth in low- 

 lands or levels, alfo in the firm rock or (lone ; and 

 lies in layers ox ft rat a, that is like a fiat-work* ac 

 between three and four fathom under a cover of 

 common (lone, about a finger thick. When they 

 would work upon it, they clear away all to the ore* 

 on which they lay wood to burn, and on the heated 

 ore pour cold water, which makes it the eafier to 

 work ; after which they break it in pieces, and con- 

 vey it on a heap together : and as all this is done in 

 nhe open air, they can only work at it in the fpring 

 and fummer feafons ; for, in winter and autumn > 

 the groove, which is very wide, and ftands uncover- 

 ed, is generally half full of {how and rain. In the 

 working feafons, twenty large iron pots or retorts,' 

 weighing between eighteen and twenty-one centners, 

 are filled only a third, as the pyrites greatly heaves 

 by the heat •, and thefe pots are placed in a vaulted 

 furnace, in manner that the bottom of the one 

 mail touch on the neck of the other ; and, on 

 both fides of the furnace, are ten apertures, five in 

 the upper, and as many in the under row. Then 

 the iron-receivers are fitted on to the pots, and well 

 fecured with luting; and fire being made under the 

 pots, the coarfe fulphur is forced off into the iron- 

 receivers at the rate of four and a half centners in 

 twenty-four hours, according as the pyrites happens 

 to be richer or poorer in fulphur \ whilft fome ot 



Z the 



