-very zeolitic. In some places the zeolite occurs in bands and seams
an eighth of an inch in thickness, but there is a marked absence of
laterite beds when compared with the other parts of the Island.
The sea has worn away the rocks to a distance of fifty feet or more
a t the beach, forming a plateau of dikes. The beach itself is formed
of loose shingle, and the ground around is covered with fragments of
a laminated phonolitic-looking dike. A greystone laminated or
schistose dike, traversed by one purely augitic, may also be seen
amongst the many varieties which occur at this spot.
I t is asserted that Manatees have been seen on shore at this
portion of the coast ; if such be true they have proved their race
to be able navigators to have traversed the tortuous passages formed
by the projecting dikes, which, running out into the sea, have
resisted the destructive action of the waves, and stand up from the
water like masses of crumbling masonry and tottering castle walls.
The naturally wild, desert-like aspect of this portion of the
Island is somewhat increased by the appearance here and there of
the dead carcase o f a sheep, and the wild scream of the sea fowl
mingled with the ceaseless voice of the ocean.
To investigate the probable age of the Island, apart from the
time occupied in building it up from its foundation to its summit,*
recourse must be had to an examination of the denuding action of
the atmosphere upon the surface, and of the sea upon the coast line ;
and although no exact estimate can be arrived at, it is possible, by
a calculation formed upon careful bases, to approximate near to it.
The possession of a peculiar fauna and flora in itself points to
very great antiquity, but its geological formation alone is sufficient to
distinguish it as perhaps the most ancient volcanic production of its
character.
I t may even still be startling to some who cling to the
idea that the world is no older than six thousand years, to be informed
that the Island is a veteran of at least eight or ten times
that period ; and that there it has stood, alone, weather-beaten and
worn, unvisited perhaps by any save wild seabirds, through hundreds
of centuries before the birth of man. But, be this as it may,
we are bound to read the Book of Nature aright, knowing well that
* At St. Helena sixty or seventy distinct flows of lava can even still be counted, and if these
occurred at intervals of a century, it would give a period of six or seven thousand years for
the building up of thé Island. • . ' ‘
v 2