THE GEOLOGY OF THE BERWICK COAST LINE 83 



some unimportant beds which, are laid bare here and there 

 from Marshall Meadows uoithwards, and which were formerly, 

 though unprofitably, worked. Travellers by rail must often 

 have noticed, about 2^ miles from Berwick, between the line 

 and the sea, the tall shaft which marks the site of the 

 old coal pit. Secondly, and, of course, the only important 

 ones, are the Scremerston coal pits, which, in the geological 

 scheme, lie below the Lamberton. These coals, though not 

 of first-rate quality, are interesting, because they represent 

 about the lowest, and therefore oldest, coal in our land. 



But now I must say a few words in explanation of my 

 reference to a geological catastrophe. If we ramble along 

 the coast from Berwick to Barnmouth, we shall notice 

 nothing bat lower carboniferous formations during the whole 

 of our walk. We shall observe limestones, sandstones, shales, 

 thin layers of coal, with here and there a trace of igneous 

 rock, which has been injected in a white hot fluid state 

 among the sedimentary beds at some time. But if we direct 

 our steps inland, we quickly find ourselves upon a totally 

 different sort of rock. At Burnmouth, indeed, almost imme- 

 diately, we come, in fact, upon Silurian "greywacke" (here 

 is a specimen), of which the rising land on the north of 

 Berwick, the whole of the Lammermuirs, and much of the 

 intervening tract, is composed, and on which the railway 

 from Berwick to Oockburnspath principally lies. If you 

 glance out of the railway carriage just before you enter, 

 and just after you leave Burnmouth Station, you see at 

 once, close to you, excellent and unmistakeable sections of 

 Silurian ; but if you alight and walk down the steep brae 

 to the shore, at that romantic little fishing village, lo ! the 

 Silurian has vanished, and you are surrounded by and tread 

 upon different rock altogether — the limestones and sandstones, 

 in fact, of the lowest carboniferous, which continue all the 

 way to the mouth of the Tweed. 



Now, the most elementary student of geology will at once 



