ANNIVERSARY ADDRESS OF THE PRESIDENT. 39 
An analysis of the subjects of the papers read during the year has 
shown a large numerical preponderance of those treating of strati- 
graphical questions. In the preceding year the preponderance was 
on the side of Paleontology. 
Of the stratigraphical papers a large proportion related to the 
Paleozoic and the Archean divisions of rocks; and of these indubi- 
tably one of the most important, both in respect of its immediate 
subject and also on account of the bearing of the author’s conclu- 
sions upon the age of homotaxious rocks in other districts, was Dr. A. 
Geikie’s paper, entitled ‘On the supposed Pre-Cambrian Rocks of 
St. Davids.” I may not claim that intimate acquaintance with the 
locality and with its petrology, without which it is not possible 
independently to form an opinion of the completeness of the proofs 
offered by the author that the three Pre-Cambrian groups of 
Dr. Hicks are, in the main, actually masses of eruptive rock of 
younger age than the ‘‘ Lower Cambrian Conglomerates ” apparently 
overlying them ; and that they are not, as Dr. Hicks thinks, in the 
main, masses of metamorphosed sedimentary rozks (with subordinate 
additions of eruptive rocks) of greater age than the “ Lower Cambrian 
Conglomerates.” The impression left on my mind, after an attentive 
consideration of the paper, and of the debate upon it, is that, having 
regard to the importance of the question raised by Dr. A. Geikie, it 
is very desirable that he and Dr. Hicks might find it practicable 
together to revisit St. Davids, a proceeding which, as it would afford 
opportunities for explaining on the spot difficulties us they presented 
themselves, would tend greatly to remove and to reconcile discre- 
pancies of interpretation, and might even result in an agreement 
upon the true order of succession and age of these rock-masses, a 
desideratum scarcely to be expected from a continuation of polemical 
papers lately promised *. 
A paper, scarcely less important on account of the question it 
raised, was that by Dr. Callaway, on “The Age of the newer 
Gneissic Rocks of the Northern Highlands.” These, which had 
usually been considered of ‘* Lower Silurian” age, are, Dr. Callaway 
contended, Archzean; and he supported this opinion by a large body 
of evidence laboriously gathered in the fieid. Having visited several 
of the localities which furnished the sections with which Dr. Calla- 
way’s paper was illustrated, I can bear testimony to the conscien- 
tiousness of his work; yet, if I may be allowed to say it, the con- 
viction grew upon me that, considering the very involved character 
of the country, no complete proof of the true sequence of its rock- 
masses is to be expected from any exploration less than a very 
detailed survey of the entire area, mapped on a large scale, and sup- 
plemented by an exhaustive petromicroscopical and chemical study. 
* A preliminary accord upon petrographical nomenclature would be essential 
to such success. The need of this isso obvious, that it would be ridiculous even 
to refer to it, had it not become apparent in the course of the debate that the 
common name “ granite” was by one party held to include rocks consisting of 
a binary mixture of quartz and felspar, and by the other party applied to the 
ternary mixture of the above two minerals with a third, usually mica, commonly 
so designated. 
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