'S2 A SYSTEM OF 
Reddifli brown; dug up in the ifland of 
Gottland in Sweden. 
ir. Pale red ; dug up at Upfal in Sweden. 
This, when burnt, is of- a yeilowifli co- 
lour, and ufed for making the earthen-ware 
in the potteries at Rorftrand near Stock- 
holm. 
SECT. XXVII. 
'2. Semi-indurated, Marga indurata aere fate^ 
* fcens. 
It is nearly as hard as a ftone when firfi 
dug up, but moulders in tlje 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. 
c. Grey. 
h. Red. 
Thefe are found at Styggforflen, in the 
parifli 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 toph^ 
ftein. 
a. White, from Woxna in Garden, and 
in the river at Nykioping in the pro- 
vince of Sodermanland. 
h. Grey, found in the provinces of An- 
germanland and Skone. 
It 
