448 ME. G. BARROW OX THE MOINE GNEISSES [Nov. I904, 



from difficulties, was a more reasonable interpretation of the sequence 

 than that adopted by the Author. He therefore inferred that the 

 Author had not proved his main point regarding the stratigraphical 

 horizon of the Hoine Gneisses. Indeed, he considered it improbable 

 that the latter were represented by a few feet, and at one locality 

 by a few inches of the Parallel-Banded series. The speaker then 

 referred to the resemblance of part of the Moine Series to the pre- 

 Torridonian sedimentary schists north of Loch Maree, and to the 

 development of structures akin to those of the Moine schists in the 

 basal division of the Torridon Sandstone. In conclusion, he expressed 

 the hope that the paper would be published with the necessary 

 illustrations, as it embodied the views of one who had studied the 

 crystalline schists in the areas mapped by him with great energy, 

 enthusiasm, and ability. 



Sir Archibald Geikie remarked that, although it had been satis- 

 factorily proved that the main mass of the rocks of the Central 

 Highlands is of sedimentary origin, great difficulties still remained 

 in the determination of their true order of succession. He had had 

 the advantage of traversing some of the Author's ground with him 

 in former years, and could bear testimony to the zeal, capacity, and 

 ingenuity with which he attacked the complex problems which these 

 rocks present. The speaker, however, thought that the difficulties 

 involved in the Author's present .theoretical explanation were too 

 formidable, and he preferred the view of the structure of the ground 

 which had commended itself to the rest of the members of the 

 Geological Survey. In the exposition of his paper given by the 

 Author that evening, no reference had been made to the Boulder- 

 Bed which formed so conspicuous a band across the Highlands, 

 although no doubt this band had been fully dealt with in the paper 

 as written. The speaker was disposed to attach great importance 

 to this horizon as a clue to the sequence of the formations. Yet it 

 illustrated some of the perplexing features of the region. Though 

 conspicuous along the northern margin of the central chain' of 

 quartzite-ridges, it had not been recognized along the southern 

 margin. But, even along its line of outcrop, it appeared not to be 

 a continuous sheet of conglomerate; it disappeared for considerable 

 distances, and came in again on the same horizon, even as far as the 

 islands of Islay and Garvelloch. Probably it represented a series of 

 local shingle-beaches which were not developed farther south. The 

 paper would be a valuable record of the observations and conclusions 

 of one of the most active and enthusiastic among the workers who 

 had given their time and energy to the elucidation of Highland 

 geology. 



Mr. Greenly felt that it was impossible at that late hour to deal 

 with the many points of great interest which were raised by this 

 paper, the question of the relation of the gneisses of Moine type 

 being one of great magnitude. In Sutherland, where the speaker 

 had worked, they certainly appeared to represent a very large 

 formation. He drew attention to the unique opportunity for 

 geological science presented by the work of the Geological Survey 



