16 
president's address. 
and described tlie Highland rocks. It is, therefore, an 
excellent instance of the power of a name and official 
position when we find the Tunes , which, of course, 
we usually look upon as omniscient and infallible, gravely 
stating, in a summary of the scientific events of the year, 
that the Geological Survey had at length discovered the 
true relations of these old rocks. 
Perhaps I may, somewhat at the risk of repeating what 
I said last year, give a general outline of the final results 
of observation. 
The unaltered rocks which occur in north-west Sutherland 
and Ross are the Torridon sandstone, the quartzite, the fucoid 
group, and the Durness limestone. This limestone, which 
contains fossils of species which point to a Lower Silurian age, 
is the newest sedimentary rock of the district, the so-called 
upper quartzite and limestone being repetitions of the corre¬ 
sponding beds mentioned above. Over this mass of rocks the 
eastern metamorpliic rocks (the so-called newer gneiss) have 
been thrust by earth movements which have of course acted 
since Lower Silurian times, andtlie schists and gneisses which 
in Sango Bay, &c., appear to lie upon the limestone have 
really faulted junctions. These correspond to the similar 
rocks in the zones of pressure schists in Eriboll, about ten 
miles to the south-east. Up to this point there is now sub¬ 
stantial agreement, but as to the nature of the metamorphism 
of the eastern series and the original material from which it 
has been elaborated there is still some difference of opinion. 
Are we to look upon these rocks merely as a division of the old 
Archaean gneisses, which, as I stated before, is the opinion 
of Dr. Callaway, or, with Professor Lapworth, consider them 
as an intimate and to some extent recrystallised mixture 
of all the rocks in existence n the region prior to those terrific 
movements of the earth’s crust which have been spoken of 
above ? In this case the planes of schistosity, lamination, and 
foliation are not planes of bedding, but of shearing and cleaving, 
along which the rocks have yielded to the lateral pressure. 
From this it will be evident that in the words of Professor 
Ijapwortli “The results already attained in the north-west 
are merely the preliminary sketches for a great and a most 
necessary work, namely, the detection of the chief laws of 
mountain stratigraphy and the discovery of the more impor¬ 
tant processes of regional metamorphism. It seems to me 
that these are the conclusions that every one who knows the 
facts is certain to draw for himself from the startling and 
sudden collapse of the brave Murchisonian hypothesis in our 
midst, and that they ought to have the effect of banishing 
