INFLAMMABLE substances are found in great abundance, within the bounds under our review. Coal (Lithanthrax) is, in Rutherglen, of the very best quality. It is commonly divided into soft and hard. Both kinds are free, and are easily broken into fragments of right angles, and clear surfaces. They burn with a bright flame; have no sulphureous smell; and leave a very small quantity of white and light ashes. None of the varieties cake in the fire. A splint, or cannel coal, of a hard compact texture is found in the main coal at Stonelaw; and in a thin stratum in Freeland, and Murrays. It takes a fine polish; is highly inflammable; and, when burnt, leaves a hard calx. It is specifically lighter than the other varieties. the coal in Kilbride, if we except the splint coal, is not nearly so good as in Rutherglen. It is not sulphureous, nor of the caking kind; but contains a great proportion of sand and clay and is kindled with difficulty.
COAL has been found no where, perhaps, in more uncommon situations than in Kilbride. Some of the Ludi Helmontii, afterwards to be described, contain good coal. But this is not the only uncommon situation in which that useful fossil has been found. A miner, in 1790, digging for iron-stone in the Basket mines, struck down a piece of schistus, in which was inclosed a small, but complete bed of coal. It was about an inch in thickness; 11 in length; and 8 in breadth, at the broadest. It gradually diminished to a sharp edge, when it was lost in the schistus. the coal was of an excellent quality; broke into quadrangular fragments, having smooth and glossy surfaces; it contained no sulphur, and burnt with a bright flame. It had every appearance of having been produced in the very spot where found.
HERE an opportunity is afforded of investigating the theories that have been given of the origin of coal. But more facts, are, perhaps, yet necessary to enable any person to form a true theory, concerning this part of the mineral kingdom.
THE purest of all the inflammables, in this country, is Petroleum. This bituminous substance oozes from the fissures of a rock of argillaceous grit, in the banks of Calder, a little below the Blackcraig. This fossil is likewise found near Gillburnsynke, in a free-stone rock that may be called a Bituminous grit; it is of a black colour; burns in the fire with a bright flame, till the pitch is consumed, when the colour becomes a darkish gray; and then the stone easily crumbles down between the fingers into pure sand. Petroleum, as shall afterwards be taken notice of, is also found in some varieties of the Ludus Helmontii. This pitchy substance is of a black colour; readily adheres to the fingers; grows hard by exposure to the air, but never so hard as jet; it is electrical; may be melted and cast into moulds; and burns with a clear flame. Bitumen, of similar qualities, oozes from the fissures of a limestone stratum, in the neighbourhood of Hawk-head, near Paisley. It is also, at Stewarton, found in a lime-stone quarry, belonging to William Cunningham of Lainshaw, Esq; It is used, with success, by the people in the neighbourhood, as a plaister for cuts and festered wounds. In Kilbride it has, sometimes, been used to besmear the naves of cart-wheels: which purpose it answers better than any artificial mixture.
WHETHER bitumens are, sua origine, minerals: or whether they derive their origin from bodies once organized, is not fully ascertained.
THIS part of the country is not altogether destitute of Sulphur. Nodules and crystals of Pyrites are sparingly found among coal, till, iron-stone and lime-stone. None of it is collected for use.
PEAT (Geanthrax) is in so great plenty in Kilbride, that it occupies a considerable number of acres. This useful fuel varies in its quality, even in the same peat-moss.1 Peats dug near the surface are light, soft and yellowish they readily consume in the fire, and leave a small quantity of a very light, and whitish coloured ash. But those that are dug near the bottom are hard and heavy: their colour, when first exposed to the air, is a faint yellow: but, owing to the absorption of pure air, in less than five minutes, becomes extremely black: they burn a long time without being consumed, and their ashes are heavy, and of a reddish colour.
PEAT-MOSSES, in this parish, are generally incumbent on clay; are about 10 or 12 feet in depth; and almost wholly free from stones and other heterogeneous substances. they abound, however, with trees of different species and dimensions. Most of the trees of different species and dimensions. Most of the trees are broken off, a little above the roots, many of which remain in the ground, in their natural position. From this it appears, that they grew on the spot where now found. Some of them retain the marks of burning, in their lower end. Similar circumstances have been observed with trees, in several places of Scotland. A few years ago, a root of a tree, with part of the trunk, was dug out of a peat-moss near Renfrew. In the trunk, a little above the root, was found sticking an iron hatchet of a very uncommon shape. Whether this antique instrument is yet preserved I could not learn.
THE slightest inspection makes it evident, that peat-mosses, if we except the trees found in them, are chiefly composed of vegetable substances, similar to these that grow on their surface. The stems of plants, at present in a living state at the top, may be traced downward, in the moss, to the depth of some feet. As the under part decays, the upper part shoots forth, seemingly with greater vigour. Such a peculiarity is common to not a few of the mosses, even in a state of petrifaction, where the under part is converted into stone.
ONE of the most uncommon productions of peat-mosses in Kilbride, is a fossil Boletus, probably of a species not now a native of Scotland. Two specimens only are all that have been discovered. One was in fragments, the other entire; and was, by a herd-boy, picked up, and kept several years, from the belief that it was a horse-hoof, to which, both in shape and size, it bears a near resemblance. To this circumstance alone it owes it preservation. The pores are visible to the eye; they are round, regular, and penetrate the whole thickness of the plant, except about ¼ of an inch at the top. They are pervious and free from all obstructions, except at the extremities; but when these are cleared away, the light shines freely through them. This is the more extraordinary when we consider, that no fewer than 5184 pores are contained in the space of a square inch. the colour is a dark brown. This curious and rare fossil, probably the only one of the kind hitherto discovered, was found near the Eldrig, in a peat-moss belonging to Mr. John Park of Rawhead, from whom I had it in a present. It must have originally been produced on the trees, over the ruins of which the moss was afterwards formed.
OF Metallic substances, in Rutherglen and Kilbride, Iron is by far the most common. It abounds in great plenty where there is coal. A few specimens of the Hæmatites, were lately found in Rawhead moor; but no veins of it have yet appeared. The most plentiful ore is the argillaceous, or iron-stone. It lies in regular strata; or in detached pieces.
THAT which lies in regular strata is not all of the same quality. The finest, with respect to texture, composes a stratum near Edwardshall. The colour is bluish: the surface, when broken, is of a flinty appearance; extremely smooth, without any palpable, or visible particles; and, when scratched with the nail, shews a trace uncommonly white. The kind that chiefly prevails is of a darkish gray, or brown colour; and the surfaces are harsh to the touch. Some strata are calcareous: of these are two kinds; one contains the exuviæ of the ancient ocean; the other not. A stratum at Mauchlanhole is, when exposed some time to the air, very regularly subdivided into small tetrahedral prisms; which, in some specimens, fall down into coarse powder. The extraction of the metal, from almost all the varieties, is attended with profit.
BESIDES the regular strata, there is great abundance of ferrugenous nodules, or iron-stone balls, as the workmen call them. They are of various shapes, dimensions and qualities: and the situations in which they are found, are not nearly the same. With regard to their shape, they may be divided into two kinds: such as have regular, and such as have irregular shapes.
TO the former belongs that curious fossil called Ludus Helmontii, Septarium, or Waxen veins. It is of a spherical shape, more or less oblate, or depressed. “Paracelsus, who had the cubic pyritæ in great esteem, for dissolving the stone, called these bodies, from their resembling a die in shape, by the general name Ludus; and Van Helmont afterwards mistaking the bodies here described, for those Ludus’s of Paracelsus, gave them in the same cases, and called them by the same name, hence the Latin name of Ludus Helmontii. The English one is acquired from the resemblance of the Tali, in some species, but of the Septa in many more, to yellow wax in colour.2
THESE very singular stones are found chiefly in Kilbride. The strata of schistus, in which they are imbedded, begin to appear near Calderwood, and extend more than a mile towards Crossbasket. Above and below them are several alternate strata of iron-stone and schistus. They lie in a regular direction, making a kind of interrupted stratum: one stone being several inches, and often a foot or two separated, by the schistus, from another. They universally lie on their depressed sides. In one stratum of till there are two rows, at a few feet distance from each other; and keeping the same direction. The iron-stone of which they are composed, is of an excellent quality; yielding about 50 per cent. of iron.
WHAT renders them a striking example of the curious and admirable structure. They are beautifully subdivided by Septa, generally filled with calcareous rhomboidal spar, or pyrites. Not a few of them contain, along with the spar, a considerable quantity of Petroleum, which sometimes fills the whole of the spaces between the tali. In some specimens, if a section is made perpendicularly, the one half of the stone is wholly subdivided with pitch, and the other with spar. Specimens of this variety are extremely rare. Besides, there is another variety, equally, if not more uncommon. Instead of petroleum the Ludus Helmontii contains coal: this, however, does not subdivide the tali, by way of septa, but runs chiefly in a horizontal direction. The coal is of a good quality; it breaks easily into quadrangular fragments, and smooth glossy surfaces; it burns with a bright flame; is not liquified by heat; is reduced to a soft white ash, and has not the smallest appearance of ever having been charred. The stones in which the coal is inclosed, are found in the same stratum with the rest, and are generally pretty large. The diameter of one, from which I obtained specimens of coal, was nearly 4 feet.
LUDI Helmontii are sparingly found at Stonelaw, in a stratum of till above coal. They are chiefly of the variety, in which the tali are inclosed with calcareous spar. The surfaces of some specimens are beautifully reticulated by the sparry septa, which are prominent above the tali, about ⅛ of an inch. In a variety, of which the above-mentioned is, probably, an example, the solid part of the stone, beyond the septa, is easily separated from the part which is subdivided by the septa. In this respect they resemble some kinds of Geodes. The separation is occasioned by a small quantity of ochre. Of this kind I found, in August 1792, several specimens in the parish of Kirkintilloch.
MANY of the Ludi Helmontii have in their center an elliptical Nucleus, round which they were, perhaps, originally formed. Its dimensions bear a considerable proportion to the dimensions of the stone. The nuclei are not so thick as broad. They are generally of a dirty white colour, resembling burnt lime-stone; and are partly crystallized. They readily effervesce with acids; and greedily absorb water; after which a certain proportion of them falls down into powder. They are inseparable from the rest of the stone, and from them all the septa seem to proceed. In some specimens they seem to be composed of concentric lamellæ.
IT appears, from various circumstances, that the septaria were formed in the stratum of schistus, in which they are imbedded. Various opinions have been given concerning the original cause of their peculiar construction: but it is more than probable, that our knowledge of the manner in which these, and many other fossils in the bowels of the earth, were formed, is too scanty, to enable us to decide positively about many things concerning them.
SEVERAL varieties of Ætites, or Eagle-stones, another kind of iron-stone balls, are found in this country. These fossils are of a round, or elliptical form; and consist of a nucleus, commonly argillaceous, surrounded with a covering of iron-stone. The name Ætites is given them from a report that Eagles put them in their nests, to facilitate the hatching of their eggs. Superstition, which is ever inventive, taught for a certainty, that, being worn by pregnant women, they had great influence in rendering labour, in childbirth, easy and safe. They are divided, according to the state of the nucleus, into male, female, or neuter. Superstition ascribed, even to this fanciful division, certain extraordinary powers, over, not only the chick in ovo, but also the human species.
NODULES of iron-stone, irregularly shaped, are to be met with almost every where. In some places they are found in regular strata, in others not. Some contain sea-shells, and are calcareous; others are destitute of shells, and are not affected by acids. They are known by different names, as Kidney-stone, Button-stone, &c. from their bearing a general resemblance to these bodies. Very few of them received their shape by attrition. They commonly contain the best of iron-stone.
FRAGMENTS of an argillaceous iron-ore, of a blood-red colour, are found at Stonelaw, and some other places in Rutherglen. This variety is usually called Keel; and is sometimes used as a cryon for drawing.
THAT Lead exists in Kilbride, is evident from some small pieces of the galena communis, that lately were picked up at the Eldrig. No vein of the metal could, however, be discovered.