illstone Grit (both of which form also the outlier of Pen-ceryg-calch
north of Crickhowell), while the lowest beds of the Coal Measures of
the South Wales coalfield are reached in the Tawe and Neath valleys
(where the beds are much folded) and near Tredegar and Brynmawr.
Glacial deposits spread over the lower grounds and striae occur at
great heights on the Black Mountains.

_Industries._--Agriculture is the chief industry, and the Agricultural
Society of the county, dating from 1755, is the oldest in Wales. About
one-fourth only of the area of the county is under cultivation, and the
chief crops grown are wheat and barley, but above all, turnips and oats.
The acreage devoted to any other crop is practically infinitesimal,
though in the eastern part more attention is paid to fruit-growing than
perhaps in any other part of South Wales. The farming is, however,
chiefly pastoral, nearly one-third of the county is common or waste
land, and its number of sheep (mainly of the Radnor Forest breed) far
exceeds that of any other county in Wales. The breeding of cobs and
ponies comes next in importance, and thirdly that of cattle, now mostly
Herefords, though Speed mentions a native breed, long since extinct, all
white with red ears. These, together with pigs, wool, butter, and (in
small quantities) cheese, form the staple of a considerable trade with
the Midlands and the industrial districts to the south and southwest.
The farms are of comparatively small size, the average cultivated area
of the holdings in 1894 being 63 acres, and the hired labour averages
about two men for each farm. A large share of the work, especially on
the highland farms, is done by the occupiers and members of their own
families, with the aid, where required, of an indoor servant or two.
Few hands are employed in manufactures, but the mining industry is more
important, coal being extensively worked--chiefly anthracite in the
upper reaches of the Swansea and Neath valleys, and bituminous in the
south-eastern corner of the county. There are also limestone and
fireclay, firebrick and cement works, chiefly on the northern outcrop of
the carboniferous limestone, as at Abernant in the Vale of Neath and at
Penwyllt.

The Central Wales section of the London & North-Western railway from
Craven Arms to Swansea crosses the north-west corner of the county, and
is intersected at Builth Road by a branch of the Cambrian, which,
running for the most part on t