452 British Association — J. Home, F.E.S., etc. — 



from sufficient to establish this hypothesis, but as it has been clearly 

 shown that there is no relation between hours and frequency which 

 holds good for all times and places, it is in this direction that 

 investigation must now be turned before we can finally say that 

 the attraction of the sun and moon has or has not an effect on the 

 occurrence of earthquakes. If it be found that there is no diurnal 

 periodicity corresponding to the tidal forces produced by them, it 

 may safely be said that any periodicity of longer period, which may 

 appear to correspond with the movements of these or any other 

 heavenly bodies, cannot be due to their attraction ; and, unless we 

 assume a hyperphysical or astrological influence of the sun and 

 planets, we must finally conclude that earthquakes are as purely 

 terrestrial in their cause as in their effect. 



n^OTiCES OIF ^vc:H!3^0II^S- 



I. — British Association fob, the Advancement of Science. 

 Glasgow, September 12th, 1901. 



Address to the Geological Section, by John Hornb, F.R.S. L. &E., 

 F.G.S., President of the Section. 



Becent Advances in Scottish Geology. 



THE return of the British Association after the lapse of a quarter of 

 a century to the second city of the empire, which since 1876 has 

 undergone remarkable development, due in no small measure to the 

 mineral wealth of the surrounding district, suggests the question, Has 

 Scottish geology made important advances during this interval of time ? 

 Have we now more definite knowledge of the geological systems 

 represented in Scotland, of their structural relations, of the principles of 

 mountain-building, of the zonal distribution of organic remains, of the 

 volcanic, plutonic, and metamorphic rocks so largely developed within its 

 borders ] It is true that many problems still await solution, but anyone 

 acquainted with the history of geological research must answer these 

 questions without hesitation in the affirmative. In the three great 

 divisions of geological investigation — in stratigraphical geology, in 

 palaeontology, in petrology — the progress has indeed been remarkable. 



The belt of Archaean gneisses and schists, which may be said to form 

 the foundation-stones of Scotland, have been mapped in great detail by 

 the Geological Survey since 1883 along the western part of the mainland 

 in the counties of Sutherland and Ross. In that region they occupy 

 a well - defined position, being demonstrably older than the great 

 sedimentary formation of Torridon Sandstone and overlying Cambrian 

 strata. The mapping of this belt by the Survey staff and the detailed 

 study of the rocks both in the field and with the microscope by Mr. Teall 

 have revealed the complexity of the structural relations of these crystalline 

 masses, and have likewise thrown considerable light on their history. 

 These researches indicate that, in the North- West Highlands, the Lewisian 

 (Archaean) gneiss may be resolved into (1) a fundamental complei, 

 composed mainly of gneisses that have affinities with plutonic igneous 

 products, and to a limited extent of crystalline schists which may 

 without doubt be regarded as of sedimentary origin ; (2) a great series of 



