ROCK. 
dom inclining to green, is the most abun- 
dant and essential portion of the rock ; a 
circumstance which distinguishes it from 
greenstone, in which the felspar predomi- 
nates, and is of a greenish colour ; whilst 
in sienite it is red or reddish. 10. Topaz 
rock is composed of quartz, topaz schorl, 
and a small portion of litliomarge : the stra- 
tification of this rock is uncommonly dis- 
tinct. 11. Quartz rock is a simple moun- 
tain rock, composed of small and flatfish 
granular distinct concretions. This, as well 
as the former rock, is not very liequehtly 
met with, nor is of considerable extent. 
12. Primitive flinty-slate is a simple rock, 
of which there exist two subspecies ; com- 
mon flinty slate, and Lydian stone. It is 
met with in considerable beds in clay-slate. 
13. Primitive gypsum, is a simple rock, 
which is distinguishable from the newer gyp- 
sum, by its being mixed with mica and 
clay-slate. 14. White stone is a rock, 
which is sometimes of a slaty, and some- 
times of a granular structure, and is chiefly 
composed of compact felspar, with a ^mall 
proportion of mica, 
Whilst the primitive mountains were still 
covered with water, it is supposed that a 
considerable rising of the waters took place, 
from which were deposited rocks of por- 
phyiy, sienite and pitch stone. These con- 
tain very little mechanical deposition, no pe- 
trifactions, and little or no carbonaceous 
matter. These rocks are considered as the 
second porphyry and sienite formations.. 
The rocks which are considered as tran- 
sition rocks are, 1. Transition limestone, 
differing from the primitive in its variety of 
colours, and by its containing the remains 
pf marine animals ; and from the floetz in its 
minute granular structure giving a splintery 
or flat conchoidal fracture. 2. Transition 
trap ; under which species we have transi- 
tion grehn stone, distinguished by being 
less crystalline than the primitive, and more 
so than the floetz; and transition amygda- 
loid. 3. Grey wack6, which is more abun- 
dant than the two preceding, and also 
marks a particular period in the formation 
of rocks, it possessing the appearance of 
mechanical deposition. There are t\vo,kinds, 
grey wack6 and grey wack6 slate: the 
former is a sand-stone, differing from, those 
of later formation, in being composed of 
portions of sand of larger size in grey co- 
loured clay-slate; the latter obtains its slaty 
structure, in a great measure, from the 
smallness of the sandy particles. This rock 
is extremely abundant in metals, and k 
very generally distributed. 4. Transition 
flinty slate. 5. Transition gypsum. The two 
latter do not appear to be decidedly dis- 
tinguished from those of the other periods. 
The floetz rocks, formed by risings of the 
waters after the creation of animals and ve- 
getables, seldom reach to a very great height ; 
those of what is termed the newest floetz 
trap formation, form, however, an exception ; 
since they , cover the summits of very high 
mountains, and show their formation to 
have been at a different period, and when 
the waters were higher than when the other 
floetz rocks were formed. Of these rocks 
limestone is the most prevalent ; and in the 
rocksof thisformation bituminous fossils, and 
the petrifactions of vegetables and animals, 
are very numerous, and in great variety. 
The rocks of this class are the following : 
1. The first sand stone formation, which is 
called ths! old red sand-stone; the grains 
are usually quartz and flinty slate, cemented 
by iron-shot clay. 2. Variegated sand- 
stone, or second sand-stone formation ; 
which is marked with, and is also disposed in, 
layers of different colours. 3. Third sand- 
stone formation; which is always white, 
and appears to be of much later formation 
than those just mentioned. 4. Partial sand- 
stone formation. 5. Floetz lime stone, is a 
simple rock, and is more distinctly stratified 
than any other rock. Two distinct forma- 
tions are described ; the first floetz lime- 
stone, and the second floetz, or shell lime- 
stone. 6. Floetz gypsum is also a simple 
rock, and is more or less distinctly strati- 
fied. Of these rocks also there appears to 
be, beside others, two principal formations, 
7. Rock-salt formation. It is mostly found 
in short, but thick, beds, in clay in a state 
between common and indurated clay. 
8. Chalk is reckoned one of the newest of 
the floetz formations. It generally contains 
flint, and the petrifactions of marine ani- 
mals. 9. Floetz trap is supposed by Mr. 
Jameson to result from a formation differ- 
ent from that which Werner has named the 
newest floetz trap, 10, Coal formation, 
Werner describes three formations of coal ; 
the oldest, or independent coal formation ; 
that which occurs in the newest floetz trap 
formation ; and that which occurs in alluvial 
land. 11. Newest floetz trap formation, 
which includes several rocks, particularly 
basalt, wack6, grey-stone, porphyry-slate, 
and trap-tuff, which are its pecidiar and 
characteristic rocks. Those which occur in 
