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the marl. The second instance occurred so lately as October 1818, on the estate of Kimmerghame, in the parish of Edrom, and near the head of that district of Berwickshire called the Merse. The bones were likewise found in a marl-pit at the depth of seven feet below the surface, which was covered with peat-moss. There was an apparent dislocation in this skeleton, the result probably not of violence, but of the gradual and unequal subsiding of the soft matter in which it was embedded; but, upon the whole, the bones were in a high state of preservation; the cranium particularly being in a much more perfect condition than that of the specimen from Perthshire. Both the fossil heads appeared to have belonged to full-grown animals. The author states, that the fossil remains discovered in Scotland appear to agree with a beaver's head described and drawn by M. Cuvier in his " Recherches sur les ossemens fossiles de quadrupedes," vol. iv. sect. "De rongeurs fossiles." The specimen described by the celebrated French naturalist was found by M. Traullé, in a peat-moss in the valley of the Somme in Picardy.

At the same meeting Mr Bald read a paper on the Coal Formation in Great Britain, illustrated by numerous sections and specimens.

Dec. 11.-The Secretary read a communication from Mr Stewart, Lecturer on Botany, giving an account of his having found and examined many specimens of the rare moss, bux baumia aphylla, and assigning reasons for believing it to be a plant of longer duration than botanists have hitherto imagined. A paper was also read by Mr Stevenson, on the original formation of the land now constituting the territory of the United Dutch Provinces.

Dec. 29.-Professor Jameson read

an account of the rocks of Sandside in Sutherland, and illustrated the description by sections and specimens. A paper on the luminosity of the sea was also read by Mr John Murray, Lecturer on Chemistry.

GEOLOGICAL SOCIETY.

The first communication which calls for notice was a paper, by W. Phillips, Esq., on the Chalk Cliffs, opposite Dover on the coast of France, read at the meeting of the society held on the 6th of November. Mr P. found these cliffs to consist of deposits similar to those between Dover and Folkstone, except that the upper part of the bed with numerous flints is not visible on the French coast. The dip of the strata is nearly the same on both sides of the channel, but the thickness as well as the height of the cliffs is much less on the French side. Mr P. thought they had once been continuous with the English beds, and formed part of what is now termed the chalk basin of London; the then connecting mass having been since washed away by the action of the sea. At this meeting also, Mr P. read a paper on the modifications of the primitive crystal of sulphate of barytes. The angles of the crystal, a right rhomboidal prism, were found by the reflecting goniometer to measure 78° 18′ and 101° 42. Mr P. observed eighteen modifications, and described the secondary planes produced by them.

Dec. 4.-A paper from Dr Day, communicated by Sir James Macgregor, on the Geology of Ceylon, was read. This island consists almost entirely of primitive rock, composed chiefly of gneiss and dolomite, rising in some places to the height of 7000 feet above the level of the sea. The mountains and plains are generally

covered with debris, and the soil, which is poor, corresponds to the rocks from which it is formed. There are hot springs in the neighbourhood of Trincomalee, the temperature of which varies from 103° to 137°. Iron is the only metal found in the island, which, however, is rich in gems; such as, tourmaline, garnet, pyrope, cinnamon-stone, zircon, hyacinth, spinelle, sapphire, &c. &c. No traces of volcanic action are anywhere visible.

Dec. 18.-A communication was read from T. Robinson, Esq. of Morley Park Iron Works, Derbyshire, on a tree found in these works. As the miners were sinking a pit for the purpose of obtaining iron-ore, they discovered a tree, apparently oak, in an erect position, its bottom standing below the third measure of iron-stone; its length was about six feet, its diameter from ten to fourteen inches, and its substance dark coloured and mouldering; its position, and the unbroken appearance of the beds it traversed, seem to countenance the idea that it grew there previous to the deposition of the beds surrounding it.

Jan. 1. 1819.-Mr Buckland's paper, "On the Geologica Structure of the South-western Coal District, and on the Relations of the Deposits by which it is partially covered," the reading of which had been commenced at the former meeting, was now concluded. The district referred to appears generally to consist of two principal formations: the first reposes on the transition rocks, and includes the independent coal formation of Werner; while the second consists of more recent horizontal deposits, lying on the transverse edges of the first formation. The first formation consists of the following beds: 1. Limestone and imperfect slate, which the author considers as the upper members of the greywacké series, and a link between the transition slate-rocks and suc

ceeding formations; 2. Old red sandstone; 3. Mountain limestone; and 4. Coal measures. The second formation consists of-1. Calcario-magnesian conglomerate, and magnesian limestone; 2. Newer red sandstone and red marl; 3. Lias; and 4. Oolite. This paper also states the angles of the inclination and direction of the different strata.

The

At the same meeting, a paper by Thomas Kent, on the Rock of Gibraltar, was read. The rock is a mass of limestone, the greatest height of which is about 1440, and its base about 2200 feet in its longest diameter. small rock on which the Devil's Tower is built appears to be a fragment detached from it: the edge of the summit is in some places so sharp that a person cannot stand upon it. Part of the rock appears to have been much broken and dislocated; and in the intervals between the fragments, as well as in a cavern in the side of the east cliff, bones of animals have been found incrusted with stalactitic carbonate of lime. The hills near St Roque, reaching to a distance of several miles into Spain, contain large quantities of oyster, cockle, and other shells. The ancient city of Carteia was built of stone quarried from these hills.

Jan. 15.-A paper was read by S. Babington, Esq.," On the Geology of the country between Tellicherry and Madras." The face of the country in general below the Ghauts is marked by low-rounded hills, composed of a porous substance, called by Buchanan laterite. The mountains denominated Ghauts, &c. the author describes as consisting of granite, gneiss, mica, slate, &c. varieties of hornblende rock, sometimes containing garnet, and in one place cyanite. The Carnatic, or country east of the Ghauts, is flat, and the soil to a considerable depth consists of strata of brown and bluish clay, interspersed

with beds of oyster, cockle, and other shells.

Feb. 19. A paper was read from the Hon. Mr Strangways on the Rapids of Imatra on the Voxa river in Carelia, and containing a notice of the bursting of the lake Loubando into the Ladoga in 1818. The greater part of the course of the Voxa may be considered rather as a chain of lakes than a river. Near Imatra it is contracted into a narrow channel within rocky banks, about sixty feet in breadth, which continues for 500 yards. Through this channel the river rushes with great fury and dreadful noise. The rock of this channel is the usual red granite of Finland, which is easily disintegrated by exposure to the weather. In 1818 one of the lakes Loubando, which discharged its waters into the Voxa, opened a passage into lake Ladoga eastward, by bursting through the isthmus of Taipala,-a circumstance that will probably alter its future geographical character.

March 5.-An extract was read from a letter written by the Reverend G. Young, Whitby, to S. Parkes, Esq. containing an account of the discovery near that place of the fossil remains of an animal, supposed to have been the ichthyosaurus. These remains were embedded in an alum rock. The skull was entire, measured two feet ten inches in length and one foot in breadth at the broadest part, and tapered to a point like a bird's beak. The jaw-bones were twisted, the teeth broken and displaced, and the remainder of the skeleton mutilated and imperfect. It is supposed that the animal must have been fourteen feet long.

At this meeting also a paper was read from H. T. De La Beche, Esq. On the Rocks and Fossils of the Coast extending from Brideport Harbour, Dorset, to the castern point of Tor

bay, Devon. This line of coast, beginning at its western point, consists of the following beds which dip eastward: 1. Rock marl, or red conglomerate: 2. Green sand: 3. Chalk, into which the green sand sometimes passes. The more remarked fossils are, ichthyosaurus, nautili and ammonites, pentacrini, trochi, casts of turbinated shells, pectens, gyphites, anomiae, and other bivalves, &c.

April 2.-The reading of Mr Hennabis' paper, begun at the previous meeting (March 19.) On the Plymouth Lime stone, was concluded. This bed generally rests on clay slate, and rises about 100 feet above high water mark. It runs nearly east and west for several miles, and dips towards the south or south-west: its breadth is from a quarter to half a mile, Many organic remains are found in it, chiefly madripores, tubipores, millepores, trochites, pentacrinites, collaties, &c.

An abstract of a letter from Dr Nugent, of Antigua, to the President, was read, accompanying some specimens of the Barbuda limestone, and containing some remarks on the geology of that island and of Antigua. Barbuda consists of a hard level limestone, with scarcely any vegetable mould upon it, which is supposed to be of the same formation with that of Antigua. The more mountainous parts of the latter island consist of trap rocks, on which rests a series of stratified conglomerated rocks, consisting of a clayey basis, containing minute crystals of felspar and spots of chlorite. On this reposes an extensive limestone formation, the lower part of which contains a great number of silicified fossils of various kinds. These islands, and some others in the vicinity, are conceived to afford evidence of the existence of a recent formation, contemporaneous with, or perhaps even posterior to the Paris basin.

May 7.-The "Description of the Valley of the Ligovca," by the Hon. Mr Strangways, was read. The river Ligovca, or Doordorovca, issues from the lake Doordoroff, fifteen miles to the south-west of St Petersburgh. At a short distance from this lake, it is expanded into a second, and finally discharges itself into the Gulf of Finland, through a marsh which is daily increasing in extent. In the upper part of its course the bed of the river. is composed of limestone; but when it leaves the second lake it passes into a channel of blue clay, and its banks are covered with an accumulation of gravel. The heights on the west side of the valley consist of limestone. The lower beds of limestone pass into upper strata of green schist, and as they approach the schist they acquire a green colour. The fossils of the limestone are principally orthoceratites, and trilobites.

An extract of a letter from Mr D. Scott, was then read. It contained an account of some marine remains, that had been laid bare by the river Brahmaputra, near the north-east frontier of Bengal. The Garton hills, which are in the vicinity of the Brahmaputra, are of two formations; the first, which occasionally rise to the height of from 2000 to 3000 feet, consist of granite, with veins of quartz and felspar; the second, which rest upon these, seem to have been deposited from water, as their strata are nearly horizontal. It is under or through one of these latter that the bed of shells appears to extend.

May 21.-A paper by the Right Hon. Lord Crompton was read, entitled, "A Description of the Rocks which occur along a portion of the south coast of the Isle of Mull." These are what are called the Carsey Rocks. The shore is composed of basaltic columns, which rise in some places to the height of 500 feet. There

are two very remarkable arched rocks: one of the openings is about 60 feet high, and between 50 and 60 feet wide. It is formed in a basaltic rock, resting on green sand, and does not contain any fossils.

June 4. The reading of Mr Taylor's paper, "On the smelting of Tinores in Cornwall and Devonshire," begun at last, was concluded at the present meeting. The author observes, that tin-ore is found in two states, in veins accompanied by other metals, or in detached fragments dispersed through alluvial matter: these are respectively known by the names of mine-tin and stream-tin. Mine-tin is first subjected to the process of dressing, by which a considerable part of the extraneous minerals, as well as the earthy matrix, is separated. The metal produced from this kind of ore is called block-tin, and is less pure than that from stream-tin, in consequence of some remains of other metallic substances, of which it is very difficult entirely to deprive it. Stream-tin has no other metallic ore mixed with it, except occasionally a little hæmatitic iron. This furnishes the graintin of commerce. In dressing minetin it is necessary to have it very minutely pulverised, in consequence of its being so intimately dispersed through the matrix, a large part of which, from the great specific gravity of the ore, may be removed by washing. It is then smelted in the common reverberatory furnace, mixed with Welsh culm and lime, and expo. sed to a very strong heat, so as to reduce the whole to a state of perfect fusion. As tin-ore consists merely of an oxide mixed with a quantity of extraneous matter, the only objects to be attended to in smelting are to reduce the earthy matter to a state of perfect fusion, to which the lime contributes, and to remove the oxygen, which is effected by the coal.

The produce of the smelting furnace is considerably impure, and the metal afterwards goes through the process of refining, which consists essentially in fusing the tin at a low heat, insufficient to melt the other metals with which it is mixed. When sufficiently pure, it is cast into moulds and sold under the name of block-tin. The reduction of grain-tin proceeds upon a different principle. After being dressed, it is carried to what is called the blowing-house, in which the metal is reduced in a blast furnace by means of charcoal. The blast furnace consists of a cylinder of iron standing on its end, into the upper part of which the ore and charcoal are thrown; the blast is admitted by a hole near the bottom, and the metal, as it is reduced, flows out at another hole on the opposite side. The metal obtained from these furnaces is farther purified by having pieces of charcoal soaked in water thrown into it while melted. The water is thus rapidly volatilized; and, as it appears, by the agitation it occasions, all the impurities are carried to the surface, where they are easily removed.

June 18.-Some additional remarks by Mr De La Beche, on the Fossil animal called ichthyosaurus, concluded the business of the season; the society not meeting again till November.

SOCIETY FOR THE ENCOURAGEMENT OF ARTS, MANUFACTURES AND COMMERCE.

Since the commencement of the session in November last, this society has been occupied in adjudging rewards for various useful improvements in the arts and manufactures; a few of which we shall now briefly notice.

The society's gold medal was adjudged to Mr Hardy, for his inverted pendulum, an instrument which the celebrated Captain Kater had previously made known to the public, by a paper in the transactions of the Royal Society of London, entitle d "An Account of Experiments for determining the length of the Pendulum vibrating Seconds, in the latitude of London." In conducting these experiments, Captain K. is said to have derived advantage from Mr Hardy's instrument, "in proving the stability of the support for his pendulum." Whether this be correct, we cannot say, as we have not had access to the original paper in the transactions of the Royal Society; but in a very ingenious and able article on Captain K.'s experiments on the pendulum, in the number of the Edinburgh Review for September 1818, no mention whatever is made of Mr Hardy's instrument, the whole credit of the invention of the convertible pendulum being ascribed to Captain K., who is said to have first reduced to practice the theorem formerly demonstrated by Huygens, that the centres of suspension and oscillation are reciprocally convertible.

The Society awarded the silver medal and ten guineas to Mr A. Bell, for his invention of a new Chuck to the Lathe.

Mr T. Taylor's Repeating Alarum, for which the sum of fifteen guineas was awarded, has been found of great service in the Royal Observatory, in giving the astronomer timely warning of the passage of certain stars, either by day or night, and thereby affording him opportunities of making observations which might otherwise be lost.

The Society voted its silver Isis medal to Mr Fayrer for his improvement on the three wheeled clocks,

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