SIMMONS— EVIDEJfCE OF GLACIAI. ACTION" IN SCOTLAND. 165 
evndences of such a movement, wliich must have taken place in the 
period when the climate was colder than at present, and which, if not 
paroxysmal, was sufficiently rapid to have entombed alive the testa- 
ceous inhabitants of the sea, and to have covered them up to a con- 
siderable depth with beds of finely laminated clay, which could only 
have been formed at the bottom of the sea." The current or rush of 
water made the ice bearing the erratics cut and polish the sandstone 
in the neighbourhood. This rush of water was doubtless produced 
by one of those earthquake waves thus described by Mr. ISmith in 
the above-mentioned work, and considered by him to be the force 
that originated the till or boulder clay : — "A rush of water, such as 
that produced by earthquake waves, of sufficient violence to tear up, 
not only the pre-existing unconsolidated cover, but considerable por- 
tions of the subjacent rocks, and perhaps obliterate the inequalities 
caused by disturbances in the coal measures, passed over the island 
from west to east, or, rather, from the north-west, depositing the 
whole in a confused mass on the surface. In that part w hicli was 
under the sea, beds of gravel, sand, and clay were deposited. In 
process of time, a second debacle swept over the island in the same 
direction, but with much less violence than the first ; the stratified 
beds, perhaps of no great thickness, were swept away, leaving, how- 
ever, occasional patclies sufficient to attest their existence, and also 
part of the pre-existing diluvium, reducing the inequalities and 
grinding the exposed surfaces of tlie rocks and boulders, for it is to 
this second debacle I ascribe the scratching of the rocks and boulders; 
and here, I think, ice acted an important part, and was probably the 
principal agent in grinding down the substance over w hich it passed. 
A colder climate and a north-west direction both point to a frozen 
ocean, which was perhaps broken up by the convulsion which caused 
the diluvial wave, and the ice of which was swept over the land in 
the same direction." Antiquaries formerly imagined the erratics, 
or the boulders termed rocking stones, to be the workmanship ot 
human hands ; now however, IMr. AVright, one of the most talented 
of tlieir number, asserts that they are the result of n:;tural causes. 
Geology has proved this ; and the same science has also taken from 
the territory of archaeology some of the stones said to be complete 
cromlechs, the Lifts being an instance. 
When examining the boulders 
near Loch Ken in Kircud bright- 
shire, I observed among many of 
great size and gigantic in composi- 
tion, one 10 feet in height, and 13 
feet 9 inches long, resting on two 
small boulders, prismatic in form. 
(Seesketch.) AV^orkmenwere blast- 
ing some of the boulders when I was measuring, consequently their 
number is decreasing ; and the evidence ot glacial action in the neigh- 
bourhood of Loch Ken, as far as boulders are concerned, will soon cease 
to exist. This, however, cannot be said of the striking glacial action 
