52 REPORT OF MEETINGS FOR 1901 



While these shallow-water conditions prevailed here, vol- 

 canoes broke out after having been long in active operation 

 in other districts adjoining. As regards the position of the 

 centres of eruption it is not easy to state anything definitely ; 

 but, as the vents before mentioned were undoubtedly those of 

 volcanoes at a somewhat later period, it would appear that we 

 should be safe in regarding the site of the volcanoes from which 

 the materials of the tuffs seen near Canty Bay were emitted 

 as coincident with one or other of the three. Probably North 

 Berwick Law represents the site of the principal one; The 

 Bass is another, and a third is represented by Traprain Law. 



There is no need to enter into any great detail regarding 

 these volcanic outbursts. Suffice it to say that, so far as 

 the district specially under notice here is concerned, all the 

 earlier eruptions were certainly of an explosive character. 

 And if any one will attentively study the details of the strata 

 so formed, as these are exposed in the cliffs and on the 

 shore at Canty Bay, he may easily satisfy himself that 

 occasionally the explosive eruptions were of a very violent 

 character. It would be as well for him to remember that 

 the huge blocks, some of them many tons in weight, which 

 he may see in the tuffs on the shore, have each and all of 

 them been hurled forth from one or other of the volcanic 

 vents in question, and after a journey into the air, which 

 may, in many cases, have been one of thousands of feet, they 

 have fallen back to the surface of the Earth. He will see, 

 along with these other strata which afford evidences of quiet 

 periods, when only fine dust was ejected ; and here and there 

 he may see vestiges of the old pools which had come into 

 existence on the flanks of the cones, and into the soft mud 

 at the bottom of which big blocks now and then had fallen 

 from the skies. He may also see dykes and intrusive sheets 

 of rock, representing the efiFects of the subterranean action 

 of the old volcanoes. Lastly, some very curious sand dykes are 

 there laid open to view. These have perpetuated the memory 

 of some surface cracks formed in the velcanic rocks by earth- 

 quakes, which have subsequently become filled from above 

 with sand, or other material, which has since hardened into 

 stone. All these, and much more that is of interest, may 

 be seen along the shore on either side of Canty Bay. 



