Mr. WiNCB on the Geology of the Banks of the Tweed. II7 



No. XV. — Remarks on the Geology of the Banks of the Twees, from 

 Carham, in Northumberland, to the Sea Coast at Berwick. By N. J. 

 Winch. 



Read July 20, 1830. 



The rocky strata which border the Tweed from Carham Bourn, where 

 the river begins to form the boundary between Northumberland and 

 Scotland, to the sea shore at Berwick, appearing to be associated in a 

 manner so different from the order generally considered by geologists 

 as the natural arrangement, will oblige me to abstain from theory alto- 

 gether in the following remarks. It is, therefore, my intention to lay 

 before the Society merely a series of notes lately made during an ex- 

 amination of the north-eastern termination of our district, accompanied 

 by specimens to assist in verifying the correctness of the observations. 

 A superficial view of the banks of this beautiful river presents a suc- 

 cession of eminences, I can scarcely call them hills, chiefly composed of 

 Diluvium, containing numerous Basaltic boulders, water-v/orn, as usual. 

 This soil is red ; but colour does not always indicate the nature of the 

 rocks below, for a red soil also covers the Porphyries and Syenites of 

 the north of England and the south of Scotland. By a cut on the side 

 of the road immediately beyond Coldstream Bridge, the incumbent mass 

 of loose earth is shown to be not less than fifty feet thick, at that spot, 

 from the top of the bank to the road, and for fifty feet more, to the brink 

 of the stream, no rock is seen to crop out from under the debris ; and 

 subsequent remarks led me to think that this part of the country was 

 generally clothed by a diluvial soil of considerable thickness. To avoid 

 repetition, it may not be amiss to enumerate the rocks which are the sub- 

 ject of these notes. Excluding Basalt, they are all stratified, and, with few 

 exceptions, dip towards the southward of east, but at very different 



VOL. I. R 



