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GEOLOGY Pre-historic Man.—Examples of flint arrowheads, scrapers, polished stone axes, and the various other implements used by Palæolithic and Neolithic man have been found very generally distributed, more especially on the moorlands bordering on Yorkshire, where they occur under the peat. A fine series of these, collected by Dr. Colley Marsh, Mr. Parker, and others, is to be seen in the Rochdale Museum, and many collections are in private hands.

The abundance and widespread character of these implements point to Lancashire having been well populated by Early Man, whilst the finding of the bones and teeth of the red deer, ancient British ox, and other animals shows that the fauna was of a more varied nature than is now the case.

ECONOMIC GEOLOGY

Useful Minerals.—The opening pages of this paper made mention of the many and great industries carried on in Lancashire, and dependent more or less upon the character of the geology.

It now remains for us to consider what the mineral wealth consists of, and to what extent it is utilised.

Coal.—The chief source of mineral wealth is of course coal, which is mined over the whole of the coalfields. The thin seams of the Lower Coal Measures have been to a large degree worked out, the only seam of any importance remaining to be exploited being the Gannister, and that portion of it more especially which is united to the overlying Bullion seam to form the Mountain Four-Feet. This latter seam lies around the fringe and beneath the whole of the Burnley Coalfield, and has been comparatively little worked. The coal is bituminous, and not so good as in the Gannister proper, but as the seam is of greater thickness than the latter, and may improve when followed deeper, it is extremely likely that it will be increasingly used in the future. All the seams of the Lower Coal Measures have been, and are now, where mining in them is still carried on, worked solely for local consumption, the many factories and industries and the homes of the people supplying a constant and near market.

The main source of the coal supply is the Middle Coal Measures, the seams of which are thicker and contain much better coal than is found in the Lower Series.

The potential yield of the Lancashire Coalfield has been estimated by Professor Hull and others on several occasions, and lastly by a Royal Commission on Coal Supplies. The investigations of the latter, based upon the evidence supplied by mine managers, engineers, and geologists, lead to the conclusion that most coal seams of a thickness of twelve inches and upwards can be safely, and in all probability profitably worked down to a depth of 4,000 feet. The finding of the Royal Commission can be best expressed in tabulate form as follows:—

Tons of Coal remaining unworked in Seams of Coal which are:

Estimated Quantity not capable of being worked due to Barriers required to be left or for support of Surface Buildings, etc.:

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