128 
THE BASALT OF ROWLEY REGIS. 
circumstances of atmospheric or sub-aerial influences. Take 
an instance. The native blocks already referred to are what 
we might call weathered—that is, the colour is altered from its 
original blue to a warm buff, partly perhaps by the de¬ 
composition of the felspar contained in the exterior parts 
liable to be acted upon, but much more so by being stained by 
ferruginous or other matters in the moist materials in contact 
with them. And so it is with the true stone in the quarry; 
wherever you see a joint—no matter whether it is stone against 
stone or stone against a roclie parting—then you see the 
uniform rich buff colour. In both instances the discolouration 
extends to about a similar depth. Now it would not be quite 
safe, I suppose, to argue from this that the exterior colouring 
of both blocks and rocks dates from the same period; and yet 
I am inclined to think that such is the case, because when I 
search my favourite old walls—the very oldest of them—or 
even when I examine some of the many huge blocks which, 
from their ponderous size, have been allowed to remain where 
placed by Nature countless ages ago, what do 1 find ? I find 
that when any stone or block has been fractured, subsequent 
of course to its fracture of detachment from the solid rock, no 
discoloration, no weathering, has taken place; that, instead of 
the buff colour of blocks and joints in quarry, the fractures 
show a black face, and therefore that no weathering has 
taken place during the centuries or milleniums in which they 
have been exposed ; and I deduce from this that practically 
true basalt does not weather or decay, and that the roclie is 
an entirely different substance of basaltic origin, but wanting 
in some of the component parts of true basalt, and that we 
find it in its original condition. 
I have said that directly we turn the southern shoulder of 
the hill we have no roche beneath the surface soil; the same 
may be said of the extreme tops of the various bosses of the 
range of these Eowley Hills, but the circumstances of these 
two cases are widely different. On the tops of the hills the 
roche has been removed, degraded. That it had covered these 
parts could, I think, be easily shown, even leaving analogy out 
of consideration; but as we turn southwards we find the 
roche in situ and persistent over the whole south and west 
area, only it is here covered by our bed of native blocks 
already referred to. We find, then, a general section of the 
hills would give— 
Basalt at base, 
Roclie above, covered by 
Surface soil; 
but at the apex we have a section of basalt only, the surface 
