President's Address. 



5 



how many and important are the questions which the mine- 

 ralogist has to answer, and also attempt to prove the truth 

 of my first proposition, that geology is based on mineralogy, 

 instead of being merely an adjunct. 



I have shown, in a paper which I had the honour of read- 

 ing to the Koyal Society, that the great fundamental granite 

 is most probably of aqueous instead of igneous origin. Now, 

 this very question is much more one to be answered by the 

 mineralogist than the geologist. He may indeed boast that 

 it was in the field at Glen Tilt that Hutton found the in- 

 trusion of the granite into the stratified schists ; but it was 

 to the laboratory of Hall, and to his crucibles, that our 

 Nestors owe their theory of the igneous origin of these rocks. 



Is it not, however, strange that men, who boast of their field 

 work so much, should have failed to see that the junction of 

 granites with schists, and also the union of granites them- 

 selves, should so rarely show any symptoms, however slight, 

 of any alteration or metamorphosis at the connecting edges ? 

 It seems as if men, when they have accepted a theory, adopt 

 the simple plan of never looking at any fact which may mili- 

 tate against it, and so from teacher it passes to pupil, and, 

 without hesitation, is adopted as a simple faith, and all 

 those who attempt to doubt or disprove it are charged with 

 heresy. When at the late meeting of the British Associa- 

 tion at Manchester, I took the opportunity of urging these 

 views of the aqueous origin of granite ; and although sup- 

 ported by the whole of the younger chemists and mineralo- 

 gists, I was opposed by the venerable Dr Daubeny of Oxford, 

 by the remark, "That though my theory seemed very in- 

 genious, and he was not prepared to advance any argument 

 against it, he hoped that from his age he would be allowed 

 to maintain his old faith." 



Before passing from this question of the aqueous origin 

 of granite, allow me to give you the last proof which I have 

 discovered of the truth of the theory. 



It is well known that brown quartz, which occurs so 

 abundantly in our Scottish granites, to which the name of 

 Cairngorm has been applied, from being first found on that 

 mountain, owes its brown and sometimes yellow tint to the 



