32 A SYSTEM OF 



a> Reddifh brown •> dug up in the ifland of 

 Gottland in Sweden. 



fa Pale red ; dug up at Upfal in Sweden. 

 This, when burnt, is of a yellowifh co- 

 lour, and ufed for making the earthen-ware 

 in the potteries at Rorftrand near Stock- 

 holm. 



SECT. XXVII. 



2. Semi-indurated, Marga indurata aire fate- 

 fcens. 



It is nearly as hard as a ftone when firft 

 dug up, but moulders in the open air. It 

 is moftly flatty, and is not uncommon in 

 the flate rocks of Sweden, where it lies be- 

 tween the thick beds of flatty limeftone, and 

 is is alfo found by itfelf, forming very thick 

 ftrata. It does not diflblve in water, till, by 

 a confiderable length of time, it has moul- 

 dered to a powder. 



a. Grey. 



b. Red. 



Thefe are found at Styggforffen, in the 

 parifh of Rettwick, in the province of 

 Dalarne. 



SECT. XXVIII. 



3. Indurated or ftone marie, Marga indurata. 



A. In loofe pieces, Marga indurata amorpha *, 

 * by the Germans called Duckftein, or Topb- 



fiein. 



a. White, from Woxna in Carelen, and 

 in the river at Nykioping in the pro- 

 vince of Sodermanland. 



b. Grey, found in the provinces of An- 

 germanland and Skone. 



It 



