PROCEEDINGS OF THE PERTHSHIRE SOCIETY OF NATURAL SCIENCE. 
47 
already (as in other Societies) a class of members from whom no 
annual subscription is required, and to this class some of our 
roost energetic working members belong; but it was thought 
that others might wish to contribute something to the funds, 
and that the ordinary subscription might be beyond their 
means, so the Society has empowered the Council to recommend 
a reduction of one-half the subscription in cases where this 
seems desirable, and we trust that this will be taken advantage 
of. But in return we expect that such members will be really 
working members, who, either in the way of communications, 
exhibitions, or specimens, will help to carry out the objects of 
the Society. It may be known to some of you that in the north 
of England,—especially in Yorkshire and Lancashire,—there are 
many scientific Societies composed, in whole or for the most 
part, of working men. (I use the term “working-men” in its 
ordinary acceptation, though I hold that that is erroneous, for 
we are all—or ought to be—“working men.”) Now, many of 
these North of England men are proverbially’cute, and it might 
be worth while considering, if time permitted, whether the exis¬ 
tence of the Societies is due to this ’cuteness, or whether the 
’cuteness has its origin (or is at least more developed) by the 
studies which the Societies encourage. At any rate, what holds 
good for Yorkshire should hold good for Perthshire, and it is 
probable that many working men would find it beneficial to 
themselves to belong to our Society, and the Society would gain 
strength from such members. It has, indeed, always had such 
members—in fact, some of the founders were working men— 
but what I wish to take this opportunity of expressing strongly 
is, that there is plenty room in ®ur ranks for more, and that, 
while glad to welcome all as members, we will be still more 
glad to get them as fellow-labourers in the field of science—that 
is, as effective working members. 
But it is time to bring this brief sketch of the Society’s past 
history to a conclusion. We have seen that it has, to the best 
of its ability, endeavoured to carry out the programme laid 
down by its founders nearly fifteen years ago; that in shade and 
in sunshine, through good report and through evil report, it has 
gone on steadily working for the promotion of the objects for 
which it exists; and that, with many disadvantages to contend 
against, it has (it is hoped) not been altogether—directly or in¬ 
directly—unbeneficial to the community at large. To-day is the 
beginning of a new era into which the Society enters with 
brightened prospects. To-day the Society comes into possession 
of a land flowing with many advantages almost unhoped for by 
its founders. But if these advantages are to be employed as 
they ought to be—if the future is to emulate the past—each 
member must keep steadily in view the objects for which he 
and his fellows are banded together. And it will be well if at 
the end of another fifteen years the Society can show as credit¬ 
able a past as it does to-day. 
2. “ Climatic and Geographical Changes in Post-Glacial 
Times." By Dr Geikie, F.R.S. 
The author commenced by remarking that his object 
in this paper was to sketch in outline some of the 
more noted physical changes- which had taken place in 
North-Western Europe since the close of the Ice Age 
or Glacial Period. It was necessary at the outset, he 
said, to define clearly the limits of this inquiry, and for 
this purpose he gave a comprehensive sketch of what 
are known as the glacial accumulations, and pointed 
out the succession of physical changes of which these, 
various accumulations are the record. He showed how it 
could be demonstrated that vast regions in our Continent 
had been at one time covered with a great sheet of glacier- 
ice, which covered Scotland, Ireland, and the major 
portion of England ; filled up the North Sea ; buried all 
Scandinavia; occupied the basin of the Baltic, and flowed 
south as far as the 52d parallel of latitude in Germany. 
All the mountain-ranges of Europe were at the same time 
covered with perennial snow-fields, from which enormous 
glaciers descended to the low grounds, and advanced some¬ 
times for almost inconceivable distances. Erom the ter¬ 
minal front of the ice-sheet, and from all the local glaciers 
of Central and Southern Europe, torrents and mighty 
rivers escaped, and carried vast quantities of gravel, sand, 
and mud down to the low-lying lands. Many of the low¬ 
land valleys would appear to have been wellnigh filled up 
with snow in winter time ; and this snow, becoming 
frozen into a kind of ndv^, accumulated from year to year; 
so that the rivers in summer, when they descended in 
greatly-increased volume, were enabled to rise to high 
levels, and to inundate in this manner enormous tracts of 
country. Thus the fine mud carried down from the 
glaciated regions was deposited at levels raised sometimes 
several hundred feet above the bottoms of the valleys. 
This extremely arctic condition of things by and by 
passed away, and the climate of Europe became so genial 
that the differences between the seasons were much less 
marked than they are now. The evidence for these 
changing climatic conditions was by no means confined 
simply to the appearances presented by the glacial and 
interglacial deposits themselves. Abundant remains of 
the mammals, molluscs, and plants which peopled and 
clothed our Continent in these times had been preserved, 
and their testimony confirmed and extended the proofs 
derived from a study of physical geology. Thus we found 
that while the cold climate prevailed, the arctic-alpine 
flora, which is now characteristic of Northern Norway 
and Sweden, formerly occupied the low grounds of Central 
Europe. At the same time rein-deer and musk-sheep 
lived in Southern France, the glutton frequented the 
shores of the Mediterranean, - and marmots and other 
northern and alpine animals were its congeners there. 
The land-shells then living in Central Europe tell a 
similar tale;—amongst them northern forms are most 
