18 
room vih. veyedfrom the Bay of Finland to St Petersburg!!, 
Nat. h'ist. an( l now forming the base of the equestrian 
statue of Peter the Great; granite in several 
stages of decomposition ; new or regenera a- 
nite from the Hartz, See. ; binary aggrega es, 
called Gramtels by some authors (graphic stone 
from Scotland^ Sweden) ; granite mixed with 
other minerals; such as common shorl; garnets, 
actinote, chlorite, (large polished pieces of 
granitic rocks, some of them passing over into 
sienite and poryhry)—gneiss of various approxi¬ 
mation to granite on one side, and to micaceous 
Shistus on the other; gneiss with garnets, shorl, 
&c.—micaceous shistus; the same approaching 
to gneiss on one hand, and clay slate on the 
other, (silvery variety of the latter used for 
roofing in Thuringia). 
( Dip . 6.) Continuation of the rocks com 
stituting the slate-formation. Oldest or primitive 
clay slate of several colours ; variegated (fruit 
or cuckoo) slate. Subordinate beds in clay slate : 
novaculite or whet slate, chlorite slate, drawing 
slate, better known by the name of black chalk; 
flinty slate and Cydian stone; anthracolite or 
kohlenblende. — Transition slate, mostly from 
(he Ifartz mountains, (specimen, in which 
it is seen in immediate contact with grey 
>yacke, a transition rock of the nature qf o\d 
sand-* 
