158 Bevan— Coal-basin of South Wales. 
As we gaze on this wonderful group of insular wrecks, varying 
in form from the solemn to the grotesque, and presenting now the 
same general outlines with which they rose above the Glacial Sea, 
we can scarcely resist contrasting the permanence of the ‘ everlasting 
hills’ with the evanescence of man. Generation after generation of 
the inhabitants of the valleys within sight of the eminence on which 
we stand have sunk beneath the sod; and their descendants can 
still behold in these rocky pillars emblems of eternity compared 
with their own fleeting career, but fragile and transient compared 
with the cycle of geological events. Though the Brimham Rocks 
may continue invulnerable to the elements for thousands of years, 
their time will come ; and that will be when, by another submergence 
of the land, the ocean shall regain ascendency over these monuments 
of its ancient sway, and complete the work of denudation it has left 
half finished. 
VI. On THE PuHysIcCAL FEATURES OF THE COAL-BASIN SOUTH 
oF WALES. 
By G. Pumures Bevan, Esq., F.G.S. 
HERE is not in Great Britain any coal-field so characteristic as 
that of South Wales; nor one which in outward appearance so 
little agrees with the general notion as to what a coal-field should be 
like. Instead of the barren and monotonous surface that we usually 
find in Durham, Staffordshire, Lancashire, or Scotland, we find 
scenery of a high order,—lofty hills, romantic dales, broken scaurs, 
and woods feathering down to the banks of the streams that run 
brawling to the Bristol Channel. It is a wonder indeed that tourists 
do not oftener explore these gems of South-west landscape, particu- 
larly as every valley is now accessible by railway. Nor is it merely 
in scenic interest that the basin is peculiar ; for the very physical 
arrangement which gives the hill and dale enables much of the coal 
to be won by level, instead of pit, thus forming a marked feature in 
the economy of the working. It is with regard to this physical 
geography that I would say a few words, as viewed in relation to 
the geology of the basin. 
If we look at a geological map of the district, we shall find this 
coal-basin to be of an irregularly elliptical or pear shape, with the 
broad axis of the pear forming the Monmouthshire and Glamorgan- 
shire districts towards the east and middle, from whence a rapid 
convergence westward, including the remaining part of Glamorgan- 
shire and Caermarthenshire, forms the stalk. The boundaries of the 
basin outside the limestone-escarpments are the ‘OLD Rep’ valleys 
of the Usk and the Towey on the north, east, and west; while 
the Bristol Channel forms the basis on the south. Within the 
basin the following arrangement prevails:—Sloping southward from 
rocks are of unequal softness, and though they rise up in exposed situations. In 
discrediting the wonderful extent to which certain rocks may resist the atmosphere , 
geologists do not take their mossy covering sufficiently into account. 
