the coast line now, and we should fail to recognise, in its present
form, the same Island. Atmospheric action upon the rocks, through
long' ages, bringing about gradual denudation, has reduced its
elevation, and, with the aid of heavy rains and slight upheaving
force, rendered its surface irregular; while the unceasing wear and
■tear of the restless ocean on its rocky coast has reduced its area to
almost one half of its original size.
With this figure of the Island in mind, we may next proceed to
view the effects produced by such causes, as have just been mentioned,
upon its surface ; and first in order examine the water-cut gorges
which have been already referred to as intersecting the northern,
eastern, and western portions. These ravines, the largest of which
number about sixteen, originate on the high land near the crater s
edge, but deepen and widen as they approach the sea coast, where
some of them measure not less than one-eighth of a mile across at
the bottom, three-eighths of a mile across the top, and a thousand
feet in depth. Lemon Valley, viewed from Thompson’s Hill, affords
a good type of these huge channels. The strata on each side
correspond in position so regularly, that any suspicion of their being
caused by convulsive fractures is dispelled. The passage of rain
water from the mountain tops towards the sea is doubtless the
chief agent by which they have been formed, and the process of
deepening and widening may still be seen going on during heavy
rains. The water which falls on the high land rushes down towards
the sea, and, in its course washing out the rubble and mud beds,
undermines the lava until it splits off in great fragments, rolls down,
and in its turn is carried away. Many caves, formed by the undermining
of the lava beds in this manner, may be seen along the
hillsides which enclose these ravines, and they also abound along the
sea shore where the waves have washed out the laterite beds for
many feet in a horizontal direction. Some of them constitute the
only habitations owned by fishermen ; others nearer the water level
are in consequence inaccessible, and serve only to increase the roar
of the waves as they roll in and out of them. There is a large one at
Frying-pan Cove, twenty feet in depth, and there are some situated
on the coast near Deep Valley, which are stalactitic, hut these latter
are only accessible by boat at low tide.
In this manner these channels or gorges have, in course of time,
been gradually increased in size, their enlargement doubtless being
\V ¡1111 'it'