Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/168

 156 the upper part this rock is compact. From this eminence there is a very extensive view of the coast, which presents a very irregular broken line.

In going from Redruth to Truro, by Carnon which is at the farthest extremity of Restronget Creek, we follow for some time the road to Falmouth, and for the first three miles at least there is only granite; a little before coming to the road from Penryn to Truro, and just before leaving the parish of Gwennap, the grauwacke formation begins and continues without interruption as far as Truro, its positions to the East of which town I have already described.

I passed too short a time in Cornwall, and I am not sufficiently familiar with the practical part of mining to enable me to treat of this interesting subject in detail; I must leave it to those who are more capable. I shall confine myself to a few geological observations alone, and I shall, as may be expected, follow with most other mineralogists the opinions of Werner on the formation of veins.

All mineral beds or deposits whatsoever may, I believe, be referred to one of the three following divisions.

A. Mineral beds.

B. Mineral veins.

C. Alluvial depositions.