of Edinburgh, Session 1881 - 82 . 
779 
At a later date, it became known that boulders, both numerous 
and large, were to be seen on icebergs and shore — ice floating in the 
Arctic Sea, and from which they were dropped when the icy rafts 
melted, or stranded on submarine rocks or sandbanks. To make 
this explanation possible for Great Britain, it implied the submer- 
gence of the land beneath the waters of an ocean many hundred 
feet above the present sea-level, and having a temperature greatly 
lower than that of our present British seas. 
Whilst each of these theories has its supporters, all geologists 
are agreed on one point — that for the transport of our Scotch 
boulders, many being hundreds, some even thousands of tons 
in weight, in order to be carried many miles across a country, 
some agent of tremendous power has to be sought for, of whose 
existence and operations these boulders were witnesses. Could these 
boulders speak, what curious revelations would they not give 
out ; or, could the mysterious markings on the surface of many of 
them, markings impressed whilst in transitu , be rightly interpreted, 
what important inferences as to the nature of the agent which 
carried them might not be obtained ? 
Another circumstance added to the interest of the inquiry. The 
events whose occurrence these boulders indicate must have been, in 
a geological sense, of recent occurrence. The boulders lie generally 
above all the rock-formations, and even above all the beds of clay, 
gravel, and sand, which form the surface of the country. They, 
therefore belong to a period subsequent to any of these geological 
deposits. 
Such were some of the speculations current among geologists 
when, in the year 1871, this Society resolved to appoint a Committee 
to investigate the subject. Though our Society was, I believe, the 
first in Great Britain to take this step, other societies on the Con- 
tinent had preceded us. Three years previously, Professor Favre of 
Geneva had organised a committee of inquiry for Switzerland, and 
at his instance the Geological Society of France took similar steps. 
I received several letters from the Professor, urging me to propose 
this inquiry also for Scotland. His communications having been 
made known to the Council of our Society, the result was the 
appointment of a Committee in April 1871. 
In the autumn of that year, the British Association for the 
