9S ASYSTEMOF 
d. Blue, is very common in Sweden, 
in the provinces bordering upon 
the Baltic. 
e. White, is found in the woody parts 
of Sodermanland, Dalarne, and 
of other provinces. It is often 
' found in a flaty form, with fine 
fand between its flrata. It is not 
eafy to be baked in the fire : when 
it is burnt, it is of a pale red colour, 
and is more fufjble than the pre- 
ceding ones. 
Fermenting clay, Argilla intu- 
mefcens. 
This is very like the preceding 
(^), as to the external appearance, 
and other qualities ; but when they 
are both found in the fame place, 
which is not uncommon in feveral 
of our mine countries, they feem 
to be different in regard to the fer-- 
men ting quality of this variety. 
This fermentation cannot be the 
effed: of the fand mixed with it, 
becaufe fand is found in them 
both : and befides, this kind ferr 
ments in the fame manner when it 
is mixed with gravel or ftones; 
and then it ferments later in the 
fpring than the other, fince by the 
ftones, perhaps, the froft is longer 
retained in it. . 
Mixed with lime, fee Marie, Sedion 
§ECT, 
