of the Pyrite s. 83 



at the day : by (inter is meant, in the full extent or' 

 the word, all thole earths in the groove, which, by 

 means of the gentle motion of the waters, work out 

 and exude from the Mures (whence they are called 

 gar *) and thus accumulate ; turning thick and 

 fmeary, a part hardening to done, and forming ici- 

 cles, a part remaining earthy and foft like butter, 

 according to the difference of times, place, the na- 

 ture of the earth itfelf, and other circumdances. 

 The lad fort con fids commonly of an ochry, 

 yellow and brown fubdance, and doubtlefs is only 

 the metallic earths of pyrites, fomewhere or other 

 weathered, or dilTolved •, its earth, by thatdedruc- 

 tion, becoming highly tender and light, fettles down- 

 wards on fifiures, thro' the water, and alfo mounts 

 upwards, in its tendered parts of all, to the day, as 

 is known to be the cafe of mod medicinal fprings. 

 The firft fort is more of a calcarious or fpathy 

 white, not fo common, and probably derived from 

 fome fuch rock, which, if not a pure lime or gyp- 

 fum done, yet partakes of it ; at lead, quartz 

 or the like, it cannot be : this we fee from its 

 refolution, particularly by its ignition and extinc- 

 tion \ where, by the lixivious odour, by the crumb- 

 ling and extraordinary degree of whitenefs, it be- 

 wrays its origin: again, from its compofition, when 

 the waters in vaults, and adjoining to walls, (where- 

 of, among others, the great aqueduct, called halfe- 

 brucke, near Fribourg, is a plain teftimony) let fall 

 again the lime, unobfervedly conveyed along with 

 them, and re-apply it to the roofs and fides, in 

 flakes and icicles -, yet with this difference, that fuch 

 a finter, as at the day even in places, that feem pretty 

 clofe, and yet not altogether fo, as quite to exclude the 

 air, arrives not to that degree of firmnefs and hard- 

 nefs, like what fuch a one has, that proceeds from 



G 2 grooves 



" From the German eitren, ftgnif\ing to ferment, 



