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along the edge of the precipice, what a spectacle presented itself! We saw before us the torrent, boiling, angry, throwing its masses of white

spray to the height of twenty or thirty feet with a convulsive roar. The rocks by which it rushed staggered, [!] the trees shook. Although at the height of eighty feet above this terrible convulsion, we felt the agitation of the air, and were enveloped in foam and spray.' p. 101. A little further on,

We approached the torrent of Gias, one of the largest that fall from these mountains, and passed it on foot, upon the blocks of granite which rose above its surface., A prodigious mass of waters precipitated themselves around, rolling huge fragments of ruck, trunks of trees, and whatever obstructed their passage, with a frightful noise. In passing this spot our guides told us, that a few days before it had been the grave of a poor peasant girl. Her mule, alarmed at the waters, rushed over the precipice, and was caught by the trunk of a pine, while its ill-fated rider continued falling from rock to rock, and disappeared in the boiling torrent below.'

The guides declared there was too much snow for an attempt at Mont Blanc. Was not our Author very glad to hear that ? He fully did his duty, however, we will acknowledge, on other eminences, especially Mont Anvert, the account of his ascent of wbich is bighly interesting. And, indeed, in parting with our gay associate, we will fairly acknowledge that this latter part of his book is worthy to be read even by all the literati, young and old, of the celebrated seat of literature to which he belongs. The scenes themselves have a commanding fascination : our Author will not probably lose much by our declining to distinguish and ascertain how much of their effect, in description, they owe to him.

We will conclude with one short extract.

• One evening we visited the extraordinary pass which forms the only communication between the baths of Leuck and the village of Albinen on the heights above. A perpendicular rock, four hundred and twenty feet high, is scaled by nine ladders, placed one above another, and supported only by the projecting crags. An Austrian general, whom curiosity had induced to ascend, a short time before, was so alarmed by the awfulness of his situation when upon the seventh ladder, that he was obliged to be bound hand and foot to it, till assistance could be procured to take him down, when he was carried back insensible to the village. I was glad to find myself safe again at the bottom; yet we were told that the women of the country will go up and down with a dead calf at their backs.'

Art. III. Transactions of the Geological Society. Vol. II. 4to. pp

.

558. Thirty-nine Plates. Phillips, 1814. IN one of the later volumes of the former series of our Journal,

we noticed the First Part of the transactions of this infant S

ociety, and anticipated the gratification and instruction the fr;

fiends of science were likely to receive, from the subsequent abours of its members.

The collection of papers before us, bears ample testimony to the indefatigable exertions, the pbilosophic spirit of inquiry, and (for we esteem it a feature not the least worthy of notice in a work of this kind) the moderation and candour of the gentlemen who have contributed to form the volume.

The greater part, and, we may without disparagement to the rest safely say, the most valuable part, is from the able pen of the President, Dr. Mac Culloch, who has furnished nine papers out of the twenty-four, all of which throw light upon interesting and difficult parts of the science.

As we shall shortly have an opportunity of taking a sketch of the present state of Geology, as a science, in noticing some recent publications on the subject, we shall now, without detaining our readers with any farther preamble, give a short account of the different papers, which, we trust, will be amusing and instructive, even to those persons who are not initiated into the mysteries of Floetz and transition formations.

1. On certain Products obtained in the Distillation of Woody

with some Account of Bituminous Substances, and Remarks on Coal. By J. Mac Culloch, M. D. &c.

In the preparation of charcoal for, glinpowder, a dense black fluid called tar, is produced. By exposure to heat, this fluid

. assumes the consistency, appearance, and chemical properties of asphaltunr',' Dr. Mac Culloch compares this product, with the vegetable resins and bitumen, and shews that it is a new compound, formed of carbon, hydrogen, oxygen, and azote. The carbon and hydrogen constitute its basis as of the bituinens; and the large proportion of oxygen appears to give it the peculiar properties by which it is distinguished from them.

Dr. Mac Culloch then proceeds to illustrate, from the history of this compound, the subject of the conversion of vegetables into coal, which he considers as a bitumen varying as to the facility of yielding naphtha by distillation, from the fattest Newcastle coal to the dryest Kilkenny coal, but not containing charcoal as an admixture, though the extremity of the chain or anthracite is identical with carbon, as the result of the distillation of asphaltuin is also charcoal. Afterwards he investigates the different chemical properties of lignites, as Jet, Bovey coal, &c. and concludes, that the conversion of vegetable matter into bitumen, has been effected by water, and not by fire; but that the alteration of the texture into coal, may be imitated by subjecting the lignites to igneous fusion. The coaly residuum of the wood tar contained, from the distillation having been carried on in iron vessels, so much iron, as to be a real plumbago ; and the Doctor hints at the probability of its being produced in a state fit for the arts. Lastly, he shews that this pitch of distilled wood, is the substance called bistre by painters; and describes how its tone and consistency may be improved by chemical means, a desideratum long sought after by artists.

II. Mineralogical Account of the Isle of Man.

By J. F. Berger. The central and mountainous part of the Isle of Man consists of clay slate, and granite has been found in a mine worked through this stratum near the centre of the island. On the N. W. and S. E. as well as at the southernmost extremity of the island, the grauwacke skirts the clay slate, containing, at Castle-Town, limestone, and at Peeltown and Longness, patches of the old red sandstone. At one place, the granite also rises through this stratum. The northern extremity of the island is covered with a bed of marl and sand. Lead mines were formerly worked in the island, but they are now abandoned ; and, for want of geological knowledge, here, as in numerous other places, attempts have been made to discover coal, where no known analogy would indicate its existence,

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III. On the Granite Tors of Cornwall.

By J. Mac Culloch. The Loggingrock or Logan stone, at the Land's End, has been described by most Cornish tourists, and figured by several; but few have been so well qualified for either undertaking, as Dr. Mac Culloch ; and as it is an object of equal interest to the artist, the antiquary, and the geologist, we readily transcribe his account of it.

• The general height of the mass of granite on which the logging stone is placed, varies from 50 or 80 to 100 feet, and it exhibits ali round a perpendicular face to the sea. It is divided into four summits,

one of which, near the centre of the promontory, the stone in question lies. If the whole peninsula be viewed laterally, the conformity of the rocking stone to the mass on which it stands, and to the other small stones which crown the summits, is such, that the eye cannot detect it, so perfectly it seems in its place. It is in the front

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'view only that it appears detached, as if occupying an accidental, and not its natural and original place. Its general figure is irregularly prismatic and foursided, baving at its lower part that protuberance on which it is poised So inclined is the plane on which it rentin, that it appears at first sight as if a slight alteration of its position, would cause it to slide along the plane into the sea, standing as it does within two or three feet of the edge of the precipice. The breadth of the apparent contact between the plane and the centre of motion of the stone is about a foot and a half As this support is curved only in one direction, being of a cylindrical, and not of a spheroidal figure, the motion of the ston, is consequently limited to a vibration in one direction, which is nearly at right angles to its longest dimensions. It is said that the motion is now much more limited than it has been within the memory of those who live near it; a circumstance rendered very probable by the progress of dişintégration at those points of contact where water can be detained....In the trials which I have at different times made on it, the greatest force that three persons could apply to it, was sufficient to make its outward edge describe an arc hose chord was 4 of an inch at 6 feet distance from the centre of motion. ... The weight appears to be 65.8 tons, a deduction if not precise, sufficiently accurate at least to satisfy general curiosity.'

The Cheese Wring is another object of attraction to travellers, presenting the appearance of five thick blocks of stone, balanced upon each other in such a manner, as considerably to overhang their base; and fancied, by Dr. Borlase, to have been formed into a Druidical statue of Saturn. Dr. Mac Culloch, however, satisfactorily shews, as indeed De Lucand others have before explained, that these appearances, with all the favcied stratification of granite, are owing to various stages of disintegration, to which that rock is liable when exposed to the air, exhibiting another trace of similarity between the granite and the basaltic rocks.

IV. Notes on the Mineralogy of the Neighbourhood of

St. David's, Pembrokeshire. By J. Kidd, M. D. The more interesting of these rocks belong to that well known but imperfectly described series of compounds of hornblende and felspar, commencing with syenite and greenstone, and passing over into serpentine and steatite. They are ably described by the Author, but prove the want of a nomenclature, to whose terms ideas within the reach of definition are attached.

V. An Account of the Brine Springs at Droitrich.

By Leonard Horner. These springs are in the same red stratum which elsewhere produces salt and gypsum, and is probably identical with Werner's old red sandstone. T'he sandiness of this stratuin is, how

cver, a quality so inconstant, while its colour, arising from oxide of iron, is so permanent, that we would rather adopt one of the appellations given by our English geologists, than that of German naturalists.

The brine springs at about fifty yards below the surface, and the four pits produce about sixteen thousand tons annually, at thirty one pounds per ton, including thirty pounds per ton duty. The greatest produce of a pint of the water is 2289. grs. so that it is somewhat weaker than a saturated solution of salt. Mr. Horner's analysis gives-muriate of soda or common salt 96.48, sulphate of lime, or gypsum 1. 63, sulphate of soda 1.82, and muriate of magnesia 0.07 per cent.

VI. On the Veins of Cornwall. By William Phillips.

This paper contains a considerable number of facts, collected partly from the verbal accounts of captains of mines, and personal observation, and partly from the descriptions of former authors; and is elucidated by plans of some of the more remarkable veins : but the materials are of such a nature, as not to admit of a compressed abstract; and the results do not throw any light on the impenetrable obscurity which envelops the theory of veins ; nor furnish any just grounds for establishing general rules. No spot more completely convinces the geologist of his ignorance, than the mound of rubbish round a Cornish mine.

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VII. On the Freshwater Formations in the Isle of Wight;

with some Observations on the Strata over the Chalk in the South East Part of England.

The researches of M. M. Cuvier, and Brongniart, into the geology of the neigbbourhood of Paris, have excited considerable attention. The strata are superior to the chalk; they are of limited extent, appearing to have been formed in a hollow excavated in the upper part of the chalk stratum. They are well marked by distinguishing mineralogical characters; and yet more by a multitude of reliquiæ of shells, and even of quadrupeds, in such a state of preservation, as to be referrible to their places in the system of the present creation, though almost universally differing in species.

These shells and other animal remains, appear to have been deposited, partly by the ocean, or, at least, salt water, and partly by fresh, and these depositions alternate several times. The naturalists who investigated them, were not only men of distinguished abilities, but were assisted in their comparisons, by the immense collection of the French National Mu

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