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which, in point of delicacy, infinitely transcends the best chemical reactions, and in many cases, as in the alkalies, affords a peculiarly exact means of detecting them. Soda, for example, causes the whole of the colours of the spectrum to disappear, with the exception of one bright yellow band, corresponding with Frauenhofer's line D. The spectrum preduced by the lithium compounds is also highly characteristic, and consists of two very distinct red lines, the one more intense than the other. By the assistance of these lines it has been shown that lithium, which was once considered to be one of the rarest of the elements, is very widely distributed. It is found in sea-water, the ash of sea plants, in many mineral waters, and in land plants. The milk of animals fed on wild plants contains it, and it has also been shown to exist in human blood; and it will be possible to obtain it from many sources in which, owing to the imperfect nature of the reactions previously known, its existence has been overlooked. The flames given by the compounds of barium, strontium, calcium, and potassium, are scarcely less characteristic than those just mentioned, and enable each of these substances to be detected with unerring accuracy when they are present in the minutest trace. Not only, however, is the spectrum analysis a most conclusive means of detecting the known elements, but it affords a means of discovering those which, from their existing in very minute quantity, have hitherto escaped notice; and Bunsen and Kirchoff have already detected a new alkaline metal, giving a spectrum consisting of two blue lines, and they are now engaged in the endeavour to obtain a sufficient quantity to enable them to investigate its chemical properties.

A recent investigation by Mr. Dugald Campbell has shown the very wide distribution of two metals belonging to a very different class. He has found that arsenic and antimony are very generally present in sand of rivers, &c. In fact, no specimen of sand yet examined has been found free from them, and this not in doubtful traces, but in unmistakeable quantity. It is well known that the occurrence of arsenic in the soil is by no means rare; and it is also met with in the ochery deposit frequently found in some waters; but Mr. Campbell's observations trace it back to its source, and it is probable that when the experiments have been extended, these substances will be found in most rocks.

Bousingault, who has long devoted himself to the detection of nitric acid, has also shown that it is obtained from many unexpected sources; and after having detected it in rain and snow waters, in rivers, the soil, and other substances, in which its presence is clearly due to the decomposition of nitrogenous organic matters, he has also found it in native manganese and other purely inorganic substances.

It is impossible to look at these investigations without seeing that they point to conclusions at variance with many of our preconceived notions. They show that so far from particular elements being restricted to individual portions of the earth's surface, they must be considered as all being generally distributed. In fact, it would appear that wherever we possess a sufficiently delicate reaction for any substance, its presence may be detected almost everywhere; and we cannot doubt that in those cases in which we only know substances in one or two localities, our failure to discover them elsewhere is not due to their absence, but mainly to the want of discriminative tests.

The researches on the metals, which have been a favourite subject with chemists, have this year borne their fruits, and, among others, a French chemist, M. Caron, has shown that it is possible to obtain calcium in large quantity. He finds that while the chloride of calcium cannot be decomposed by means of sodium alone, the experiment succeeds perfectly if the iodide be employed; and if heated in a close crucible, with the proper quantity of sodium, the exact equivalent of the earthy metal can be obtained. And this process is instructive; for it recalls to our minds the difficulties experienced by Davy when he first used potassium as a reducing agent. In preparing boron, silicium, and some other metals, he caused it to act upon their oxides, and he had thus to overcome a very powerful affinity. Berzelius substituted the fluorides for the oxides, and at once the reduction became comparatively easy. Oerstedt then introduced the use of the chlorides in certain cases; now we have the iodides; and there may yet be found opportunities of advantageously using some of the other compounds.

Deville has also, during the past year, prosecuted his researches into the action of high temperatures, and their application to the fusion of refractory metals, and has now, by means of sufficiently large jets of gas, alimented with oxygen, succeeded in fusing half a hundredweight of platinum, and casting it into a solid ingot. He has also devoted the experience thus obtained to the determination of the vapour density of substances of high boiling points, and has, by the use of balloons of porcelain, the points of which are fused by the oxyhydrogen blowpipe, succeeded in obtaining accurate results with substances of very high boiling points.

The applications of chemistry to the useful arts, though bearing their usual share of valuable results, do not call for very particular notice here. The subject of most interest, and which has given rise to a large number of patents, is the production of colours from aniline. By the application of different re-agents a variety of different tints of great beauty have been obtained; and though it is understood that none of them are so permanent as the original purple, they have all found uses

in the hands of the calico printer. The interest which attaches to this subject, however, appears to be mainly due to its indicating the great unworked field which organic chemistry offers to the arts. That branch of the science has accumulated an immense mass of materials, to which the attention of the manufacturing chemist has as yet been scarcely directed, or which he believes quite incapable of affording useful results. The history of aniline is a practical refutation of such views. Ten years since it was impossible to conceive any substance less likely to prove useful in the arts; and it cannot be doubted that there are many other departments of the science destined to yield as prolific a harvest of valuable applications. It only remains for the manufacturer to devote more attention than he has latterly done to the study of chemistry, by which is to be understood not a mere superficial knowledge of its elements, but an intimate acquaintance with its details, to enable him to find numerous uses for substances which at present he is inclined to rank only in the list of curiosities, although, if attention were properly directed to them, uses would soon be found for them in the arts.

Fossil Rain-markings and Fucoid Impressions on the Sandstone of Scrabo Hill, near Newtonards. By JAMES BRYCE, LL.D., F.G.S. SPECIMENS of these markings were exhibited on slabs from the Scrabo quarries, where they were discovered by Mr. Robert Young, C.E., of Belfast, in August last. The impressions of the rain-drops are sufficiently distinct and characteristic; those of the fuci were at first supposed to be the footprints of some animal, to which indeed they bear much resemblance. Both are the more interesting that this sandstone has not as yet yielded any fossils, is of uncertain age, and in these quarries is pervaded by a singular reticulation of whin dikes. The section was described in which this sandstone is embraced, and which extends from the permian beds on the east side of Belfast bay to the carboniferous limestone of Castle-Espie, near Comber. Abounding in well-marked fossils at either extremity, the beds in the middle portion are singularly barren, and hence the uncertainty as to age, though there seems little doubt that they belong to the lower part of the carboniferous formation. Among these beds borings have often been made in search of coal, but without success as yet. Rain-prints have, however, been found at a lower horizon than this-even as far down as the Cambrian rocks. The geological history of rain-markings was shortly noticed; and also those conditions of the earth's surface and the earth's atmosphere, which the phenomena attending them have brought to light.

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November 21, 1860.-The PRESIDENT in the Chair.

The following gentlemen were elected members of the Society, viz.: -Mr. David Guthrie, C.E.; Mr. John Mayer, Certificated Teacher of Chemistry; Mr. Robert Smith, Merchant; Mr. Robert Gow, Accountant; Mr. James Harold.

Mr. Cockey presented the following Abstract of the Treasurer's Account for the Session of 1859-60:

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Diplomas for new Members,..

Printing and Illustrating Transactions of the Society,

Printing Circulars of Meetings,

Salary to Society's Officer,

Fee to Officer of Andersonian University,.

Do. to Clerk for engrossing Minutes,...

Blackwood, for delivering Circulars,

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Do. in Treasurer's hands,....

GLASGOW, October 31, 1860.-We have examined the Treasurer's Accounts, of which the above is an Abstract, and compared the same with the Vouchers. We find that there is in the Union Bank the sum of £10 0s. 3d., and in the Treasurer's hands, £3 16s. 9d., together, £13 16s. 9d., to the credit of the Society at this date.

The Treasurer has also exhibited to us a Voucher which he holds for money lent to the Corporation of Glasgow, from the proceeds of the Society's Exhibition in 1846, amounting, with interest to 15th May last, to £803 6s. 4d.

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The Society appointed the following gentlemen to be its Officebearers for the year 1860-61:

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On the Geological Structure of Ben-Nevis. By DR. BRYCE. THE author had satisfied himself, on examining Ben-Nevis and the adjoining mountains in July last, that the accounts which we possess of their geological structure are defective in many respects; and as regards the views now held by geologists, very misleading to the student. A survey of Ben-Nevis on all sides, and an ascent to its summit twice, showed him that granite does not rise anywhere on the mountain or its flanks to a greater height than about 1,600 to 1,800 feet. The great mass consists of basalts, greenstones, and porphyritic traps, with metamorphic clay slate; the igneous products being very analogous to

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