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A HISTORY OF LANCASHIRE Loss in Working due to faults and other natural causes in Seams of:

Estimated net available Tons remaining unworked, 4,238,507,727.

The output of the Lancashire collieries for the year 1903 was 24,517,761 tons. At the same time there was also raised 24,442 tons of clay and shale, 190,406 tons of fire-clay, and 287 tons of iron pyrites; giving a total yield from the mines of 24,732,139 tons, and finding employment for 93,912 people.

The clay, shale, and fireclay are all used in the manufacture of bricks, tiles, coarse earthenware, and pottery. The fireclays are capable of withstanding an intense heat after they have been moulded into bricks without much material change, hence the bricks manufactured from fireclay are much used in furnaces, hearths, and other places where there is great heat.

Iron pyrites is worked for the manufacture of sulphuric acid and sulphate of iron.

Clay.—Lancashire being a most densely populated county, and the solid geology to a large extent obscured by thick deposits of boulder clay, it has naturally followed that the latter has been made good use of in the manufacture of bricks. Temporary brick-kilns are frequently established in the vicinity of large towns where building operations are in progress, the clay being obtained close to the site of the kilns by removing the surface soil. The bricks thus obtained are not so close in texture or so durable as those manufactured from the better class of shales and are chiefly used for internal walls. In many cases, the coal shales are quarried at the surface and moulded into bricks, and it is probably clay obtained not merely from the Glacial drift but also from the clayey shales which goes to make up the 1,418,340 tons of clay which represents the output of Lancashire for 1903.

Sandstone.—The main supply of sandstone in Lancashire is obtained from the Millstone Grit series, many of the beds being massive, and nearly all exceedingly durable. The sandstones of the Lower and Middle Coal Measures are worked to a less extent, those of the former, whilst of fair thickness and fairly durable, at times being even equal to the Millstone Grit, yet, being also more current-bedded and jointed than the former, can only be worked with a greater waste, and are therefore not so economical. In most cases also where Lower Coal Measure sandstones occur those of the Millstone Grit are not far off, and almost invariably at a greater altitude on the flanks or tops of the hills, from which the stone can be conveyed by its own weight down inclined rails to sidings connected with the railways which traverse all the chief valleys. Most of the stone is used for road and street paving in the large towns, or for building stones, whilst the thicker and more massive beds furnish huge blocks for engine beds, foundations, retaining walls, and structures requiring great weight and strength. Many of the beds both of the Millstone Grits and Lower Coal Measures split up into slabs of from two to four inches in thickness, and are cut up for flagstones.

The readiness with which the stone can be worked, and its nearness to the towns, accounts for one feature of Lancashire towns which often puzzles visitors from other counties: in nearly all the towns the great bulk of the buildings and dwelling houses have the outer walls built of the local rocks, houses entirely constructed of brick being not so numerous. One other feature to be seen in the agricultural districts surrounding the large towns is the prevalence of stone walls dividing the meadows, which are mostly laid down in grass. The multiplicity of these walls of dark weathered stone, and the absence of the pleasant hedgerows and earthen banks which are so common a feature in most counties, give the landscape a hard and chilly look, and lead one erroneously to suppose that the industrial districts are barren and devoid of shrubs, trees, and copse.

Sandstone quarries are numerous, especially in the hill ranges north of Manchester, which stretch on to Rochdale, Littleborough, Whitworth, and the spurs running into the Rossendale valleys. The industry is a very important one, no less than 760,534 tons being quarried in 1903.

Limestone.—The quarrying of limestone is not much behind that of sandstone in the weight of output, 612,427 tons being quarried in 1903. Much of this is burnt for lime, used in the towns or on pasturage, and a great quantity is used as building stone. In the limestone districts, the limestone is used in the construction of nearly all buildings, and also for rough walling. It thus takes the place of sandstone in other parts of the country, and being of a light grey colour the towns are much cleaner looking and more cheerful.

The Carboniferous Limestone in Lancashire is not so metalliferous as we find it in Derbyshire 28