230 REPORT OF THE MEETINGS FOR 1900 



the Silurian rocks were slowly upheaved into a great 

 upland area, which rose to several thousands of feet above 

 the sea-level. Its precise position is not known ; but it 

 probably reached its highest levels along a line which may 

 be said to coincide with that which now joins Dunbar and 

 Ballantrae. The upheaval affected a very large area, and 

 what is now Berwickshire was then distant, perhaps, some 

 hundreds of miles from the nearest sea. As a consequence 

 of these continental conditions the rainfall began to be scanty 

 and irregular; and, taking one year with another, it is 

 probable that not more than about ten inches of rain fell 

 per annum, and even that was usually precipitated only 

 during very heavy thunderstorms. No vegetation could 

 thrive under these climatal conditions ; and, as a necessary 

 consequence, animal life dwindled down to a minimum, and 

 to be probably represented only by a few highly specialised 

 forms of fish life, adapted (like the Lung fish of Queensland) 

 to live in such lakes as could hold out through the long 

 periods of drought. In other words, desert conditions set 

 in. It was under these geographical conditions that the 

 Old Red sedimentary rocks seen about Ay ton were formed. 

 These conditions prevailed for a period of sufficient length 

 to permit of the old mountain range being gradually wasted 

 away. The products wasted from the mountain areas were 

 gradually spread out by torrents far and wide, and formed 

 the sandstones and conglomerates of which these rocks 

 partly consist. 



Towards the middle of this period of continental conditions 

 earthquakes began to affect the district, and they gradually 

 increased in violence and frequency until they at last 

 ushered in volcanic conditions. Here and there all over 

 the district small volcanoes broke out, and these grew up 

 in course of time and eventually formed a great connected 

 series, which extended over a large part of North Britain. 

 It was from these volcanoes that the rocks that now form 

 the Cheviots were laid down. The same volcanoes have 

 left traces of their existence at matiy places in Berwickshire ; 

 as, for example, at St. Abbs' Head and Coldingham, at 

 Eyemouth, and even at many places around Burnmouth. 

 At the last-named place they are now represented only 



