There has been great abundance of freestone wrought, from time immemorial, in the low parts of the county of Perth, and quarries of a greater or smaller grained stone of this sort appear almost in every place, with the exception of the Carses. In the Lowlands, and near to the eastern sea, the pores and grain of it are coarser ; but as the mountains are approached, the pores are less, and the grain finer, by which these stones admit of a smoother polish. The quarry of Tullyalan parish, called Long-annat, affirds a stone of a very excellent quality. It is of a white column., admits of a smooth polish, and resists the influence of the weather. Some of the principal houses in that part of the country, as well as some of the most magnificent public buildings in the capital of Edinburgh, as those of the Exchange, the. Univer sity, and the Register-office, con'ist partly of this stone, and those found at hand. And farther, in some instances it has been carried to the continent. But the quarry of Ningoodie, in the Ca•se of Gowrie, is unquestionably the finest of this kind of any in the country. Astonishing blocks, in great numbers, are raised there, fifty feet in length, sixteen feet in breadth, and three feet in thickness. Such is the demand for this stone, both at home and abroad, that four vessels are employed in exporting it from this quarry.
Flag-stones and quarries for the working and preparing of all sorts of flags, are met with in all those situations where free-stone is found, and where it exists in rather thick strata, or layers, of some depth, which are capable of being separated by hammers, wedges, or other IlleallS. In many places in the southern parts of the island, the flags raised from such free-stone quarries are of an extremely good quality, being used in very large quantities for various purposes. Those of Cornwall and Devonshire also, in many cases, allOrd a good sort of flags. The sandstone quarries of Shropshire as, at Grinsell, near Shrewsbury, about Bridgeport!), and at Corndon-hill, near Bishop's-Castle, a. well as in the Swinney mountain, &c., where alternate beds of fine white aml red stone of this kind, of very superior quality and thickness, exist; that in the first of these situations, being twenty yards thick, aflbrds flags likewise which are of a very useful nature. Freestone flags, ton, of useful sorts, are met with in the quarries of some of the midland counties ; and they abound much in many of the freestone quarries of Lanca shire, Yorkshire, and some of the other more northern dis t•icts of the country.
The quarries of this kind become slate-stone, and furnish the white, gray, and brown slate, wherever the stone lies in thin layers, or strata, which are able to be raised and sepa rated from each other with convenience and facility. They exist in most of the above tracts, and are plentiful in some of them, especially those toward the north. The Lancashire and Yorkshire quarries, in many places, supply the white and gray sorts in great abundance, and of good qualities. Those of Westmoreland, Cumberland, and Northumberland also afford them, in many instances, of a valuable nature ; and they are equally good in the still more northern districts. There are numerous quarries of different colours of them in Clydesdale, Perthshire, Argyleshire, and the county of Inver ness, from which vast supplies are constantly raised for home and other use. This sort of slate has, however, mostly the disadvantages of being very porous, heavy, less durable, and of requiring more and stronger timber to support it than some other kinds ; being only fit for exposed climates and situations.
The quarries of the lighter and thinner kinds of slate, of the blue, green, purple, and other colours, formed from other sorts of stone, only exist in some particular districts, as those of Wales, and the northern part of Lancashire, and the adjoining counties, and in a few places in Scotland. The slate quarries of the Welch districts supply several kinds and colours in large quantities, and of good qualities ; but the dark and lighter purples are the most prevalent sorts in most of them. In Lancashire, the quarries of this kind are very
numerous in the part to the north of the Sands, as about Gothwaite-common, Kirby-moor, Conistone-hills, and Til berthwaitefells, &e., and from which very large supplies of the blue, green, and the dark purple sorts of slate are raised, and sent away for exportation, or consumed at home for different purposes. They are wrought, and the slate prepared, in somewhat different manners in different places. The Gothwaite quarries have the slate dug out from the side of the hill, and carried away. But in some on Kirby-moor, a level is driven through the ground from below, the metal being conveyed away by small four-wheeled waggons, on iron railways. Those about Conistone are mostly worked into the hills, and the metal raised and carried out from them. Some of the Tilberthwaite quarries are wrought by blasting the slate-stone, and collecting and carrying it out of them on slanting roads, hi small carts, or trucks, constructed for the purpose, of levels being below the hills, but not nearly so low as the bottoms of the quarries. Others are wrought by draught roads from the bottoms of them. One man will raise eighteen or twenty hundred-weight of slate in one day where the metal rises well, but less in other eases. In some, it is dug out by one set of men, split by another, and formed into slates by a third ; for which purposes, flat crow-bars, slate-knives, and axes are employed. The slate is divided and distinguished into three sorts, as firsts, seconds, and thirds, or London, country, and toms. In the'first. or waite quarries, the slate has a darkish purple ur black cast. In the Conistonc quarries, it has a fine blue and green appearance, and is much thinner and lighter than the other sort. The Tilberthwaite slate, in some instances, splits very fine, thin, and light, but does not cover so far as those of the Gothwaite and Kirby quarries. In some quarries a sort of rent is paid .per ton, on the slate which is raised ; while in others, a certain rent only is paid for the liberty of the royalty, and not a tonnage duty. These rents, or duties, on the workers of these quarries, are probably higher than they will bear, and have enabled the Welsh slate-dealers to under sell those of this county.
Westmoreland and Cumberland, in some instances, afford good blue and green slates. In the latter, some of an excellent quality are obtained in the quarries of Borrow dale, and inferior sorts in some of the neiahbourinc. mountains.
The county of Argyle, in Scotland, in some parts, abounds with slate-quarries, as the tracts about Esdale, from which five millions of slates have for some time been annually sold. Quarries of the same kind are also wrought in many other parts, with great benefit to the inhabitants.
Slate-quarries are found in many parts of the highlands of the county of Perth, but none in the low. The slates in some are of a purple colour, in others of an azure blue, and in a few, of a muddy, sandy, brown complexion along the cutters. It is well known where the different sorts are quarried. The veins of slate-rock seem to run from Drumlane, in the parish of Aberfoil, in a north-cast direction, to Dunkeld ; and may be traced beyond the limits of the county both ways. The azure coloured are the best metal, and rise of a greater size than any of the other kinds. Many of the buildings in different places are slated with this beautiful covering. Into the lower districts of the county, slates are imported from Esdale, and the other quarries on the west coast of the county of Argyle.
Quarries of gray slate exist in many different parts of the county of Inverness, in which the quality is very good, and well suited to the climate. In some places these slates are much preferred to blue ones, as the latter are more expensive in procuring, and though nailed on the roofs ever so firmly, are apt to be loosened by high winds, unless bedded in lime, which circumstance renders repairs difficult.