Remarks on the Transition Rocks of Werner. 93 
parts of the rock, yielding to the action of the weather, 
were reduced and carried away. 
We thus find, that the granite of Cornwall possesses the 
eharacters ascribed by Werner to that of the highest anti- 
quity. Some inferences may likewise be drawn, in corro- 
boration of its title to be classed with rocks of this descrip- 
tion, from the nature of the metallic veins by which it is 
traversed. 
In the German account of the relative ages of metals, 
tin is the third, and wolfram the fourth in ‘order of anti- 
quity*. If veins containing these metals be considered in 
other countries as indicative of rocks of the oldest primitive 
formation, the same application must be made to those of 
Britain. 
I may now ask, If this be not the oldest granite, where 
are we to find it? as it appears to me impossible that any 
substance can more decidedly concur with definition. ln 
the Alps, Dr. Berger must have learnt what primitive gra- 
nite meant; yet not a doubt escapes him, of the Cornish 
being any ‘thing e else. Distincticns either do or do not 
exist; if they do, character must be attended to; if they 
do not, it is quite unnecessary to add the terms Secondary 
and Tertiary to a substance possessing every attribute of a 
primary variety, merely because the structure of an ad- 
Joining rock does not accord with a specific theory. 
Grauwacke, or, as I shall in future call it, Killas, I have 
before noticed, is a rock composed of fragments more or 
less comminuted, which must have existed in another state 
before they assumed their present arrangement. Along 
with the strata formed of these, beds of limestone are 
found, containing indications of organic remains, These 
are not confined solely to the limestone, they occur also in 
the killas; a fact which may be witnessed at any time, 
either in the neighbourhood of Coniston t, or on the right 
bank of the Black water, a little below Fermoy, in the county 
ef Cork, (Nos. 66, 67.) The formation of this class of 
rocks was therefore “subsequent to the formation of living 
animals, whose existence is supposed to be proved by the 
occurrence of organic remains in the composition of the 
tock. 
In Cornwall, in Westmoreland, in Gallow ay, and in the 
* Jameson’s Mineralogy, vol: iii. p. 275. 
+ Since | read this paper, I wrote toa friend at Coniston, requesting that a 
few of these specimens, wel! characterized, might he sent me: some of w hich’ 
are deposited, along with the rest, in the eabinet of the Society, (No. 64, 
65.) 
6 counties 
