The following were elected to be of the Council for the ensuing year :--Edward Barnard, Esq.; H. T. Colebrooke, Esq.; Major-General T. Hardwicke; Daniel Moore, Esq.; and Philip B. Webb, Esq.

An extensive and interesting series of the various species of Rhubarb from Chelsea Garden was exhibited by Mr. Anderson. The Anniversary Dinner of the Society took place at Freemasons' Tavern, and a considerable number of the Fellows, including many from distant parts of the kingdom, participated in the pleasure of this meeting, which was alloyed only by the absence, owing to indisposition, of their highly esteemed President, whose excellent qualities, great attainments, and invaluable labours for the promotion of science, have long endeared him to those who know him, and especially to the lovers of Natural History. The chair was filled on this occasion by the venerable Prelate, who from the first foundation of the Society has been one of its most zealous supporters.

June 1.-The reading of Mr. Vigors's paper was concluded; and that of Messrs. Sheppard and Whitear's Catalogue continued.

June 15.—The meeting of this evening, which was an extremely numerous one, was honoured by the presence of His Royal Highness the Prince of Saxe-Cobourg, and several other personages of distinction.

The reading was commenced of a paper, On the Structure of the Tunicata; by W. S. Mac Leay, Esq. MA. FLS. and the Society then adjourned, over the summer recess, to meet again on the 2d of November next.

ASTRONOMICAL SOCIETY.

May 14.-The whole of this sitting of the Society was occupied by the reading of the conclusion of Mr. Baily's paper On the Method of determining the Difference of Meridians, by the Culmination of the Moon; this paper having been commenced at the last meeting in April.

The author, after briefly alluding to the nautical methods of determining the longitude, including those by means of chronometers, adverted to five distinct astronomical methods which have been pursued, viz. 1st, By the eclipses of Jupiter's satellites. 2dly, By eclipses of the moon. 3dly, By eclipses of the sun. 4thly, By occultations of the fixed stars. And 5thly, By meridional transits of the moon. The first three of these, by reason of their infrequency and obvious sources of inaccuracy, are of very limited utility; while the fourth method is rendered uncertain from its involving a doubtful datum, the compression of the earth, as well as other difficulties which the author pointed out. He then proceeded to point out that the fifth method was greatly superior to any of the others, in which

opinion he was supported by the testimony of Dr. Maskelyne, Bernoulli, and many eminent astronomers who were quoted. Notwithstanding its high recommendations, this method has not been successfully adopted in practice, and has even led to some awkward anomalies, on account of its having been customary to take the moon's centre reduced to the meridian, and to compare it with the apparent places of stars passing the meridian about the same time in any parallel of declination.

The newly proposed method consists in merely observing with a transit instrument, the differences of right ascension between the border of the moon, and certain fixed stars previously agreed upon, restricting the observations to such stars as differ very little in declination from the moon, and denominated moon culminating stars. The attention of astronomers has been called to this method by M. Nicolai, of Manheim, in several numbers of Schumacher's Nachrichten. It is quite independent of the errors of the Lunar Tables (except so far as the moon's horary motion in AR is concerned). It does not involve the quantity of the earth's compression. It does not require a correct knowledge of the position of the star observed, nor does an error of a few seconds in the clock sensibly affect the result. Hence much trouble is avoided, many causes of error precluded; besides all which, the method is universal.

GEOLOGICAL SOCIETY.

May 21.-The reading of the paper " On the Geology of the Ponza Islands in the Mediterranean; by George Poulett Scrope, Esq. MGS. was concluded.

The Ponza Islands lie off the coast of Italy, opposite Terracina and Gaieta. They consist of Ponza (anciently Pandataria), Palmarola, and some islets; Ventotiene and San Stefano connect them with Ischia. The harbour of Ponza is excellent. Dolomieu's Memoire sur les Isles Ponces excited curiosity, but is too general to satisfy it. These islands are composed of rocks, of the Trachytic series, and presenting fine sections along their coasts, enabled the author to clear up many doubts and errors which the mere investigations of inland localities have caused to be affixed to this formation.

The Isle of Ponza is long and very narrow, and is eroded by the sea into deep concavities. Harder masses left along its shores show that it once was broader, and protruding ledges mark its former connexion with Quannone and La Gabbia. Prismatic trachyte, variously coloured and disposed, forms the ossature of the island. It is constantly accompanied by, and alternates with, a semi-vitreous trachytic conglomerate, formed of minute pulverulent matter enclosing fragments of trachyte. The prismatic trachyte seems to have been forcibly injected through the conglomerate, and wherever it touches the latter New Series, VOL. VIII.

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its earthy base is converted from two to thirty feet deep into a pitchstone-porphyry; sometimes it becomes a pearlstone, at others encloses a true obsidian. These rocks are connected with a silicious trachyte, resembling in appearance the silicious buhrstone of Paris. Resting on the semi-vitreous trachyte and forming the base of the Montagna della Guardia, is a rock 300 feet thick, which the author distinguishes mineralogically from common trachyte, and proposes to call greystone.

In Jannone the trachyte overlies a limestone, which Brocchi describes as transition limestone; at the point of contact this latter becomes dolomite. Having described the whole of this group, the author terminates his paper by connecting their geological structure with that of the neighbouring continent of Italy.

A paper was read, entitled, "Notes accompanying Specimens collected on a Journey through Part of Persia and the Russian Tartaries;" by James B. Fraser, Esq. MGS.

June 4.-A paper was read, entitled, " "Description accompanying a Collection of Specimens made on a Journey through the Province of Khorosan in Persia;" by J. B. Fraser, Esq. MGS.

On quitting Teheran, the road passed by the roots of the chain of Elburz, through the pass Gurdunee, Sirdara to Semnoon and Shahrood, over gravelly hills, having to the south a salt desert, and appearances of salt on all sides; thence by Mey Omood, Abbassabad, Muzenoon, and Subzawar to Nishapore, about 40 miles west of which place are found the celebrated torquoise mines, which are worked along the sides and ridges of a narrow valley. The principal mine is called Abdool Rezakee. The calaïte is found pervading a soft yellow stone and a mouldering reddish rock, as also a rock of much firmer texture resembling quartz rock of a grey colour with reddish streaks, and containing specular iron. A conglomerate rock occurs in the vicinity. The mineral is found sometimes in veins, sometimes mammillated in fissures, and at other times irregularly dispersed through the rock. The author describes all the mines actually worked; they are the property of the crown, and were valued, when Mr. Fraser visited them, at the annual rent of 2000 tomauns of Khorosan, or about 35007. sterling, and are farmed to the highest bidder. At Derroad, 25 miles from Nishapore, the primitive rocks of Elburz appeared similar to those seen in the lofty range between Ispahan and Cashan.

A paper was then read, entitled, "Geological Observations on the Sea Cliffs at Hastings, with some Remarks on the Beds immediately below the Chalk;" by T. Webster, Esq. Sec. GS.

This paper commenced with a geographical description of the cliffs on each side of the town of Hastings, from the White Rock on the west to the end of Fairlee cliff on the east, which

form a very instructive natural section of an elevated tract in Sussex, surrounded by, and coming out from under, the clay of the Wealds.

These cliffs consist of alternating beds of sandstone, shale, and clay, more or less charged with oxide of iron, and carbonized vegetable matter. The iron is most abundant in the lower part, where there are beds of two or three inches thick of rich argillaceous iron ore that were profitably worked before the fuel of this part of the country became scarce.

The middle beds of the cliff have much less iron, the greatest part consisting of very white friable sandstone. In the upper part of the series, there are many large blocks of a grey calciferous sandstone, the surfaces of which exhibit a mamillated structure: and this rock may be considered as a variety of the chaux carbonatée quartzifère of Haüy, having much analogy with the crystallized sandstone of Fontainebleau. The mamillated appearance is very well seen at the white rock, and has (though erroneously) been usually attributed to the action of the sea upon the fallen blocks.

The fossils, in the cliffs of Hastings, are not numerous; the shells being confined to two or three species of small bivalves, and a univalve resembling that in the Petworth marble. Thin layers of lignite are frequent, and fragments of a very singular silicified wood of the monocotyledon kind, the cavities of which are filled with minute transparent crystals of quartz.

Bones of large Saurian animals, and of birds, also occur, though rarely, together with scales of fish.

The author observed, that the grey calciferous rock has not hitherto been noticed in any part of the formations between the chalk and the Purbeck, except in this district; and from its not being co-extensive with the rest of the ferruginous sand series, and the want of continuity and correspondence in many of the beds, he took occasion to remark, that it may be frequently more correct to consider the subdivisions of some formations rather as irregularly lenticular than as tabular

masses.

June 18.-A paper was read entitled "Notes on Part of the opposite Coasts of the English Channel, from Deal to Brighton, and from Calais to Treport;" by Wm. Henry Fitton, MD. MGS.

This paper was accompanied by a connected series of views or elevations of the coast, drawn by Mr. Webster, from the place where the chalk rises near Calais, to where, after being cut off near Blanc Nez, the chalk again appears upon the shore near Treport; and, on the English side, from the rise of the chalk near Deal, to where it sinks at Brighton. The author expresses his acknowledgments to the Baron Cuvier, through whom he obtained permission from the French authorities to

pass along the coast by sea, and experienced everywhere the greatest attention from the officers of the French customs. The paper briefly describes the leading geological features of the coast, reciting the partial descriptions already published, and referring, for an account of the cliffs near Hastings, to a memoir by Mr. Webster, read at the last meeting of the Geological Society; and for a detail of the beds which form the cliffs from Gris Nez to Equihen, to an account of the lower Boulonnois to be read at a future meeting. From Equihen to the mouth of the Somme, the coast is altogether occupied by dunes of sand, the sand hills being, in some places, especially in the vicinity of Etaples, more than 100 feet in height. These hills are, in general, somewhat crescent shaped, the back of the crescent being turned towards the prevailing wind, and the slope on the lee side much more rapid than the opposite one. The immediate base of the dunes seems to be peat, which is found both on the land side of them, and without, just on the verge of the sea, and in some places, below the level of high water but no rocks have yet been discovered along the coast beneath the dunes. A list of heights obtained by the barometer is subjoined to this paper, and some detached sketches are annexed to it of interesting geological appearances on the French shore.

ARTICLE XIV.

SCIENTIFIC NOTICES.

CHEMISTRY.

1. On the Nature of the free Acid ejected from the Human Stomach in Dyspepsia.

OUR readers know from the notice of the proceedings of the Royal Society in the Annals of Philosophy (Feb. 1824), that in December last, Dr. Prout read a paper before that learned body, the object of which was to prove, that the acid usually found to exist in the stomach of animals, during the digestive process, is the muriatic. An acquaintance of mine, who occasionally suffers severely from dyspepsia, and was somewhat sceptical as to Dr. Prout's conclusions, lately requested me to examine the fluid ejected from his stomach during a violent dyspeptic paroxysm the day before, with the view of ascertaining the nature of the free acid it contained.

The fluid which had been thrown from the stomach in the morning, fasting, when filtered, was perfectly clear, and nearly colourless; it gave a decided red tint to litmus paper. I distilled about six ounces of it almost to dryness, at a gentle heat, receiving the product in three separate and nearly equal portions.