Vol. 52.] BASALT-PLATEAUX OF NORTH-WESTERN EUROPE. 405 



the eye cannot detect any datum-line by which to estimate the loss. 

 In the north-eastern part of the Faroe Isles, however, the horizontal 

 bars of bare rock are continued from cliff to cliff across the deep fjords 

 into the adjoining islands. These terraces afford not only a demon- 

 stration that vast hollows have been excavated out of one great 

 volcanic plateau, but also a measure of at least the minimum 

 amount of material so removed. 



Availing ourselves of these datum-lines, we easily perceive that 

 in many parts of the Faroe Isles the amount of volcanic material 

 left behind, stupendous though it be, is less than the amount which 

 has been removed. Thus the island of Kalso is merely a long 

 narrow ridge separating two broad valleys which are now occupied 

 by fjords. The material carved out of these valleys would make 

 several islands as large as Kalso. Again, the lofty precipice of 

 Myling Head, 2260 feet high, built up of bedded basalts from the 

 summit to below sea-level, faces the north-western Atlantic, and 

 the sea rapidly deepens in front of it to the surface of the submarine 

 ridge 200 to 300 feet below. The truncated ends of the vast pile 

 of basalt-sheets which form that loftiest sea-wall of Europe bear 

 testimony to the colossal denudation which has swept away all of the 

 volcanic plateau that once extended farther towards the west. 



Nevertheless, enormous as has been the waste of this plateau of 

 the Faroe Islands, we may still trace some of its terrestrial features 

 that date back probably to the volcanic period. Even more distinctly 

 than among the Western Isles of Scotland, we may recognize the 

 position of the original valleys and trace some of the main drainage- 

 lines of the area when it formed a wide and continuous tract of land. 



A line of watershed can be followed in a south-westerly direction 

 from the eastern side of Yidero, across Boro to the centre of Ostero, 

 and thence by the Sund across Stromo and Vaago. From this line 

 the fjords and valleys diverge towards the north-west and south-east. 

 There cannot be any doubt that on the whole this line corresponds 

 with the general trend of the water-parting at the time when the 

 Tertiary streams were flowing over the still continuous volcanic 

 plain. Considerable depression of the whole region has since then 

 sent the sea up the lower and wider valleys, converting them into 

 fjords, and isolating their intervening ridges into islands. 



The topography of the Faroe Islands seems to me eminently 

 deserving of careful study in the light of its geological origin. There 

 is assuredly no other region in Europe where the interesting problems 

 presented by this subject could be studied so easily, where the 

 geological structure is throughout so simple, where the combined 

 influences of the atmosphere and of the sea could be so admirably 

 worked out and distinguished, and where the imagination, kindled 

 to enthusiasm by the contemplation of noble scenery, could be so 

 constantly and imperiously controlled by the accurate observation 

 of ascertainable fact. 



Discussion. 



The President, after complimenting the Author on the clearness 

 of the exposition of his views, said that from his descriptions we not 

 only obtain a view of these old volcanic vents and lava-flows, but 



