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 Eoyal 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 metam.orphosis 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 brow^n and sometimes yellow tint to the 
