The leases in Argyleshire are generally granted for a short period, and the rent demanded for lands is truly exorbitant. This is, in some cases, owing to unjusti fiable measures taken by avaricious landlords, to excite their tenants to offer more than a possession is really worth ; but is chiefly to be attributed to the great increase in the price of cattle within the last Is years, which has led landlord and tenant to form extravagant expectations as to the future, and induced the tenant to take lands at a ruinous rent, upon the speculation, that some subse quent rise of markets may render his bargain advan tageous. The small number of other employments which this county can afford, by creating a keen competi tion for farms, also tends to enhance their price. As these causes are temporary in their nature, it is to be hoped that in a few years the rent of lands will be better proportioned to their real value ; and that the duration of leases will be considerably extended. At present the tenant is kept destitute of the funds necessary for con ducting any spirited improvements, and has no prospect that the capital expended in executing them shall be returned to him before the expiration of his lease. We have the utmost satisfaction in mentioning, that the con duct, both of the present and late dukes of Argyle, to their tenants, has been regulated by the most liberal and humane principles: without seriously diminishing their revenues, they have uniformly let their estates on such conditions as ensured the prosperity of their dependants. We are sorry that we cannot extend the same praise to all the other great proprietors.
The mineral productions of Argyleshire, arranged ac cording to the order of their relative importance, are— Lime, found in almost every part of the county ; that found at Lismore is of superior quality ; besides being a white, firm, and durable cement for buildings, it pos sesses the valuable property of becoming hard under water, which renders it peculiarly fit for canals and har bours. A hard slate, of a deep blue colour, is nearly as abundant as the lime ; the best quarries are at Easdale and Balachulish, from which immense quantities are ex ported to the low countries of Scotland. Veins of lead are frequent in the limestone and other strata ; mines of this mineral are wrought to a considerable extent at Strontian and Islay ; in which last place a vein of cop per is also wrought. Coal pits have been wrought near Campbeltown for many years. The coal was at first of very inferior quality, but we understand that of late a bed of good coal has been discovered, and opened with success. Seams of coal also occur in Mull, and differ ent other parts of the county ; but so situated, that the returns would not defray the expence of digging, and of conveying them to market. It is probable, however, that a skilful search would discover several strata of coal which might be wrought to advantage. Several other minerals, which at present are entirely neglected, may, at some future period, become sources of wealth to this county. Such as vast quantities of bog-iron ore ; several kinds of marble ; porphyry ; jasper ; rock-crys tal of various shades; garnets, generally embedded in mica slate ; sand-stone, white and gray ; and small quan tities of quicksilver.
The strata of Argyleshire present an aspect more in teresting to the geologist, or scientific mineralogist, than to the practical miner. The confused and broken state of the strata, the great variation in their inclination, and the sudden transitions from one species of rock to another perfectly distinct, while they damp the hope of finding connected veins of ore, seem to point out this as a district in which those powers which govern the mi neral kingdom have acted with more than usual energy, and where we might expect them to leave more distinct traces of their nature and mode of operation. This fine field for observation has, however been almost entirely neglected. Those observers who have communicated the result of their researches, have been either so wed ded to the volcanic hypothesis, as to class vitrified forts, sand-stone, pudding-stone, whin-stone, Ste. indiscrimi nately under the denomination of lava ; or so occupied with the inspection of minute specimens as to neglect examining the grander mineralogical features of the country.
We hope that professor Playfair will dispel this ob scurity, by publishing his observations on this county. Endowed with an experienced and critical knowledge, fitted to detect the minute differences between minerals, and a philosophical mind to perceive their general relations, and to trace the theoretical inferences to which these relations lead, his remarks on the mineralogy of Argyleshire would be peculiarly instructive and inter esting. In the mean time, the writer of this article
hopes that an account of some appearances which he ob served about four years ago, may not, in the absence of better information, be disagreeable to the reader ; and that his having then paid attention to them merely from curiosity, without any prospect of publication, may form an excuse for the scantiness of the materials, and the small tract of country from which they are collected.
In travelling along the coast of Lorn, from Appin house to the extremity of Craignish, a distance of about thirty-five miles, in a straight line, the lowest rock which can be perceived, and on which the others are superin cumbent, consists of alternate strata of slate and a deep blue stone, generally fit for making lime, but sometimes graduating into a stone of nearly the same external character, which does not readily effervesce with acids. We shall, however, to avoid circumlocution, class them under the denomination of limestone. At first sight, these strata appear to be nearly vertical, and inclined to the horizon at different angles. But, after viewing them in different directions, and comparing them with one another, we perceive that the strata have really an incur vatcd form similar to waves, or a series of arches ; and that those which we mistook for vertical strata, are merely the remaining abutments of arches, whose upper curvature has been demolished during the lapse of.ages. In favourable situations, we discover strata, which can be traced through a series of several arches ; but, in general, so little of the rock is exposed, as to render this ex tremely difficult. The arches sometimes rise with an uniform curvature, 20 feet or more in height, and 50 or 100 feet in span ; at other times, their height and span do not exceed three feet ; and the strata, in descending from the summit of the wave, are bent back in such a manner as to have a nearer resemblance to folds or plaits in a piece of cloth, than the circular curvature of an arch. The ridges of the waves run, with very little de viation, from north-east to south-west. The outline of the coast, the ranges of hills, and the lakes and branches of the sea, follow nearly the same direction ; from which we.may infer, that these waves have entirely determined the form of the country, or that the same cause which produced the waving in the strata, also fixed the height and boundaries of the land. The lower strata are gene rally limestone, from an inch to between one foot and a half to two feet in thickness, separated by beds of slate, whose thickness varies from three feet to a thin film, scarcely one-tenth of an inch; above these arc frequent ly placed inimL,nse masses of slate, rising to more than 100 feet in height. Where the strata consist chiefly of limestone, with few or very thin strata of slate interpos ed between them, the arches or waves in the strata are diminished in height and breadth, but more in the latter. The curvature at the summits and hollows of the waves is more acute relatively to the magnitude of the whole wave, and the thickness of a stratum is frequently five or six times greater at the summit of each wave, and at the hollow where it begins ascending to form the next wave, than at the'intermediate point where the contrary flexure takes place. When, on the other hand, slate strata of considerable thickness are interposed, the arches are larger, their curvature is more circular, the limestone strata preserve their thickness nearly uniform, and the thinning at the point of contrary flexure always takes place at the expense of the slate, so that we have sometimes seen slate strata two or three inches thick, in other parts reduced to a mere film at this point. Wherever the flexure is great, the limestone strata have fractures through their whole thickness, and pa rallel to the axis of curvature or summits of the waves. When the fractured stratum is of great thickness, or when those adjacent are limestone, there is in general one large fracture near the greatest flexure, filled with a vein either of quartz or calcareous spar ; but when the stratum is thin, and enveloped by strata of slate, there are numerous small fractures tending to the centre of curvature, and filled sometimes with thin veins of coarse slate. Besides these, there are other fractures traversing the strata at right angles to the former, and which, by breaking their continuity, prove that their own origin is referable to a later period.