turned out to be so enormous. Their real knowledge amounts 
simply to this. At the time when certain creatures lived 
under the sea in a certain place, certain rocks were formed 
at the sea-bottom; certain rocks were formed after these, 
inasmuch as they were laid above them; and during the 
period of this newer formation, certain other creatures lived 
above where those older rocks now he. We do not know 
that the older rocks continued to lie exactly where they were 
formed, when the newer rocks were being formed above 
them. We know that certain rocks dip at a certain angle 
and rise to the surface at a certain angle too, sometimes the 
same as that at which they dip ;— but we do not know that 
they form always such a curve as may be drawn m following 
this angle of dip and rise. The variations of position and 
contortion are innumerable, and our ignorance of the unseen 
depths is perfect. 
But the ignorance which, so far as we can see, prevails as 
the depths, is clearly traceable among geological ideas of the 
surface. We may give, in passing, a notable instance ol the 
evidence that it is so. One of the most influential theories in 
that class which has been used against ordinary scriptural 
ideas, is that usually called the glacial . It is given as the 
true account of the formations embraced m e ou ei 
clay/' which means so much in geology. It is thus briefly 
but clearly stated by Page.-He says: "After the deposition 
of the lower tertiaries, it would seem that the latitudes of 
Britain and the North of Europe underwent a vast revolution 
as to climate, and that some new arrangement of sea and land 
took place at the same period. At all events, the large mam- 
malia of the earlier tertiaries disappeared, and the land was 
submerged to the depth of several thousand feet, for we now 
find water-worn boulders on the tops of our highest hills, or 
at all events, at an altitude of from 1,800 to 2 000 feet. A cox 
period ensued, and icebergs laden with boulders and gravel 
from other regions, passed over these latitudes, and droppec 
their boulders on the then submerged lands. ¥ 11S im 
mense ocean then gave place; and upheave! land with masses 
of ice pressing down the mountain- sides, and laying snm&i 
loads of boulders and clay at the sea-bottom, to be raised by 
fresh elevations, gave existence and character to the boulder- 
formations of the present surface. He says, ' It is thus ■ that 
we find granite and gneiss boulders from the Scottish High- 
lands now spread on the plains of Fife and Midlothian, and 
blocks from the hills of Cumberland spread over the m °ors o 
* Page’s Advanced Text-Book , pp. 233, 23o. . 
