Page 99 - The snake's pass

OX KNOCKSACAR. 87
its west side — great sloping tables of rock suddenly
ended by a wall of a different stratum—a sort of
serrated edge all the way down the inclined plane ; you
could not miss seeing it, for it cuts the view like the
teeth of a saw! Now if the water, instead of rising to
the top and then trickling down the old channel,
which is still noticeable, had once found a vent on one
of those shelving planes it would gradually fill up the
whole cavity formed by the two planes, unless in the
meantime it found some natural escape. As we know,
the mountain is covered in a number of places with a
growth or formation of bog, and this water, once ac-
cumulating under the bog, would not only saturate it,
but would raise it—being of less specific gravity than
itself—till it actually floated. Given such a state of
things as this, it would only require sufficient time for
the bog to become soft and less cohesive than when it
was more dry and compact, and you have a dangerous
bog, something like the Carpet of Death that we spoke
of this morning."
" So far I can quite understand." said I. " But if
this be so, how can the bog shift as this one has un-
doubtedly done? It seems, so far, to be hedged with
walls of rock. Surely these cannot move."
Sutherland smiled. " I see you do apprehend ! Now
we are at the second stage. Did you notice as we
went across the hill side that there were distinct beds
"
or banks of clay?
"
" Certainly ! do they come in ?