WATSON — THE HEMATITE DEPOSITS OF GLAMOKQANSHIRE. 241 
THE H^MATITP: deposits of GLAMORGANSHIRE. 
By Dr. J. J. W. Watson, F.G.S., F.S.A., Member of the North 
of England Institute of 'Mining Engineers. 
During the last few years, the native iron-making resources of 
South Wales have received considerable assistance from the re-dis- 
covery and working of some very remarkable deposits of haematite in 
the county of Glamorganshire. I propose in the present article to 
describe two of the most important, perhaps, of those veins of ore, 
which are found in tlie districts of Llautrissant and Llanharry, near 
Cowbndge, and at Newton Nottage, near Bridgend ; — the iron-ore in the 
latter locality being associated with a very large and curious deposit 
of manganese, chiefly psilomelane. Prefatory to this description, it 
may not be out of place to give a few remarks on the physical geology 
of the surrounding country, inasmuch as this district possesses ample 
materials to engage the attentive and careful examination of the 
geologist, particularly in relation to the origin of the mineral deposits 
in question. The exploitation of these hsematite-mines will have the 
effect, commercially, of giving a great development and increased 
prosperity to the iron-manufacture in the district south of Cardiff ; 
while, as a social result, their being worked will probably bring back 
to a population, at present agricultural, the mining and metallur- 
gical occupations of the ancient fore-dwellers on the soil, and, what 
is most desirable, give constant occupation to a very large number 
of the working classes. 
The stratigraphical position, as well as mode of occurrence of the 
ore, is similar in all three localities, being coniined to the uppermost 
beds of the carboniferous limestone, immediately below where, in 
ordinary cases in this district, it is overlaid by the sub-dolomitic or 
calcareo-magnesian conglomerate, of equivocal age, which occupies the 
hollows and ovei'Iaps the edges of the 'limestone. 
Starting from the shores of the Bristol Channel, the limestone- 
strata roll forward to form a series of east and west anticlinals, before 
