WERNERIAN SOCIETY.

At the meeting of this Society on the 3d of December, there was read a communication from Captain Brown, of the Forfarshire Militia, describing five new species of shells, observed by him in Ireland. The description was accompanied by excellent drawings. A mineralogical communication from Mr. Giesecke was read, in which he described several new and rare minerals observed by him in West Greenland.

At the meeting of the 17th of December, the Secretary read a letter from Mr. Scott, at Ormiston, addressed to Lauder Dick, Esq.; containing a description of the junction of the transition and floetz rocks near Jedburgh, and mentioning the occurrence of granite in Roxburghshire.-Professor Jameson read the first part of a paper describing the mineralogy of the south district of Scotland, including a particular account of the rocks which occur in the neighbourhood of Dunbar, in East Lothian. The coast of Dunbar exhibits an alternation of the old red sand-stone with rocks of the trap formation; and interesting illustrations of the supposed chemical nature of sand-stone, and of the contemporaneous formation of masses of lime-stone in sand-stone, and of trap in sand-stone. At the same meeting, the first part of a memoir on the nature of the polar ice, by Mr. Scoresby, was read.-Specimens of sandstone, brought from Berskiming, in Ayrshire, by Mr. Miller, were exhibited. When cut into long thin bars they possess considerable flexibility, which is a good deal increased when the stone is wetted.

ARTICLE XIV.

SCIENTIFIC INTELLIGENCE; AND NOTICES OF SUBJECTS
CONNECTED WITH SCIENCE.

I. Phosphuret of Ammonia.

M. VOGEL has lately made a curious experiment in Paris. He put a piece of phosphorus into ammoniacal gas, and then exposed the phosphorus to the solar rays. A black matter was formed, which was conceived to be a combination of phosphorus and ammonia.

II. New Expedition into Africa.

We understand that the British Government are at present projecting a new expedition to explore the interior of Africa. They are to employ in this expedition the black regiment which has been formed on the west coast of Africa; and which, being inured to the climate, will constitute a better and more efficient guard to the travellers, than the same number of British troops. It is at present the most probable opinion, that the Niger, after running east for a considerable way, takes a southerly, and at last a westerly direction,

and runs into the Atlantic on the coast of Guinea. It will be very singular if this opinion be confirmed. It would be of great importance if the travellers would carry with them a set of portable barometers, in order to determine the elevation of the country through which they pass. If we knew the elevation of the banks of the Niger, it would be easy to determine whether the opinion of the ancients, that it is a branch of the Nile, be possible or not. Nothing in Mungo Parke's travels would lead us to suppose that the elevation of the banks of this river is great. In that case it must either flow into an inland sea, or discharge itself into the Atlantic.

III. Communication between the Blind and the Deaf and Dumb., Dr. Guillié, Director of the Royal Institution for the Blind, at Paris, by a method of his own invention, has been enabled to establish an immediate and perfect mode of intercourse between blind and deaf and dumb persons. These two species of unfortunate individuals, between whom nature appeared to have placed insuperable barriers, may, thanks to the ingenious author of this invaluable discovery, henceforward draw near and perfectly understand each other.

The first trial of this ingenious practice was made at a numerous and public meeting, held at Paris, the 26th of last August. A sentence was dictated to one of the deaf and dumb, named Masuen, a pupil of the Abbé Sicard, and by him communicated to one of the blind, who immediately repeated it in a loud voice; and he in his turn communicated to the deaf and dumb the sentence asked by the public, who instantly wrote it on a tablet.

We are assured that Dr. Guillié intends coming to London in the winter, to make an experiment of his practice before the Royal Society.

IV. Swinestone at Building Hill, Durham.

I am informed, by Mr. Sowerby, that some of the Building Hill stone retains its foetid odour for years when scraped, while This shows us that I was not other specimens lose it very soon. mistaken when I called it Swinestone, on the spot. But the reason why some specimens soon lose their odour remains still to be given.

SIR,

V. On the Solar Spectrum.

(To Dr. Thomson.)

Since my last communication it has occurred to me, that if Dr. Herschel's position respecting the heating rays attendant on the prismatic spectrum stands in need of any confirmation, the wellconducted experiments of Mr. Leslie on radiant caloric substanMr. L. distinctly affirms tiate them in a most remarkable manner.

that he found the greatest intensity, or, as I should call it, the focus of heat, by his reflectors, half an inch within, or nearer to the mirror than, the optical focus. As far as I can judge too, from

the numbers stated by Mr. L., the progress of the differential thermometer from and towards the mirror, indicates the very ratio that the prismatic spectrum displays with regard to intensity of light. What then must be our conclusion, but that the reflector in this case performs an office similar to that of the prism? *

Now, Sir, may we not take advantage of this instrument to obtain a better knowledge of those rays termed deoxidating? In conformity to my theory another focus remains to be discovered, where muriate of silver would be found to blacken most readily; for I contend, that those rays are mere modifications of heat, or, to speak more fully, that they are rays of latent caloric, or the true phlogiston; while those which affect the thermometer are obvious or sensible caloric. With the greatest respect,

I am, Sir, Yours, &c.
DAVID HUSTON.

VI. Position of Port Jackson, New Holland.

From the observations of Captain Flinders, it appears that Cattle Point, on the east side of Sidney Cove, is in latitude 33° 51 45.6", south; longitude, 151° 11' 49", east.-Flinder's Voyage, I. 237.

VII. Chinese Paste,

The method of making paste in China is much more economical than the mode followed in this country. Were it universally adopted by trunk-makers, book-binders, and others, who use great quantities of paste, it would produce a very material saving of flour, which in years of scarcity might be of the greatest consequence. The following formula used in China was lately communicated to the Right Hon. Sir Joseph Banks, Bart., by a gentleman at present in Canton. Mix together bullock's blood and quick-lime, in the proportion of one pound of the latter to 10lbs. of the former. It becomes a stiff jelly, in which state it is sold to the consumers, who beat it down with an addition of water into a state sufficiently fluid for use. At Canton it will keep five or six days in the hot weather and ten or twenty days in the cold. In Britain it would probably keep longer.

VIII. Chinese Method of casting Sheet Lead.

The Chinese method of casting sheet lead is very simple. Two large flat tiles are used for the purpose, covered on the inside with thick paper. The workman opening them a little at top, pours in a small quantity of melted lead, and pressing the tiles together with his foot, forms the sheet. A kind of resin called dummer is used to prevent the oxydizement of the metal. The tea canisters

* As sound (a) is reflected as well as light and heat by a concave mirror, I have little doubt but that their analogy will be one day perfectly demonstrated.

(a) Query. Is the focus of sound at the same distance from the reflector as the focus of light?

which have a crystallized appearance, and which at Canton are called cho yeip, or bamboo leaf, from their resemblance to that leaf, are formed from tin in the same way. They are not made in the neighbourhood of Canton.

IX. Hauy's Crystallography.

It gives us great pleasure to state, that Mr. Larkins, N° 14, Gee Street, Somer's Town, has commenced teaching the mathematical part of Hauy's theory of crystallization. It is scarcely necessary to observe, that without a correct knowledge of the mathematical principles from which this most beautiful theory has been deduced, very little progress can be made in the study of crystals. Mr. Larkins has likewise cut in wood very beautiful models of all the crystals described by Hauy in his System of Mineralogy. Complete sets of these models are sold at the rate of from thirteen pounds to fifteen pounds sterling, according to the kind of wood from which they are cut.

X. Table of Temperatures.

M. Guyton Morveau has been employed for many years in constructing a pyrometer of platinum to measure the higher degrees of heat. He was induced during his experiments to compare it with the mercurial thermometer, and with Wedgewood's pyrometer, The following table* exhibits the result of his experiments.

If I remember right, Wedgewood's clay pieces were baked in a red heat. If this be the case, it is impossible that the boiling point of mercury, which is below the commencement of Wedgewood's scale, can be represented by 20 of that scale. There is reason to believe from this, that Morveau was not in possession of the true clay pieces of Wedgewood. If so, his determination of the value of Wedgewood's degrees cannot be considered as correct. The melting point of tin is certainly stated too high in the preceding table. Mr. Crighton of Glasgow, whose accuracy is uncommon, found that this metal melts at 442°, and that it melts at a lower temperature than bismuth.

XI. Saccharometer.-Thermometer.-Starch-Sugar.-Passage of Air through Tubes.

I beg to make some observations on the queries in your Annals, of September, respecting the use of the saccharometer in brewing, which I had delayed.

According to the common acceptation of the word strength, in beer or ale, the saccharometer foretels it sufficiently near the truth, for similar processes in the same brewhouse; but it is not a sure guide for any dissimilarity in the mode of brewing or of drawing the extract for then the constituents of malt are not often dissolved in the same proportion to each other; and, in all cases, the extracts are superior in value according to their priority. For, let the first, from the same parcel of malt, be reduced to the specific gravity of the last, and equal quantities of each will give a beer or ale very different in quality.

The quantity of alcohol increases during fermentation, as the specific gravity of the fermenting fluid diminishes, but in what ratio, no correct experiments have as yet ascertained. The term, designated strength, in malt liquors, depends, however, on many inexplicable circumstances; I fancy, from the variety in quality in different beers, made from equal extracts in every respect. I do not mean to, allude to the mixture of any deleterious drugs, because I really believe the common brewers, in general, do not, and those extensive establishments in London, cannot, make use of any substitute for malt and hops. The gentleman, who makes those queries, is perfectly correct in asserting, that the common saccharometers do not give the quantity of solid matter contained in a barrel of wort; they express merely the difference of weight between that and a barrel of water. The former, however, can be ascertained nearly by multiplying the latter by 2, 7, according to my trials, which I hope agree with the experiments of this gentleman.

It is rather a disgrace to the present state of chemistry, that the chemical brotherhood of Europe should still suffer the variety in the thermometric scale to exist; I therefore, as an humble individual, beg to suggest, that a resolution, published by the leading chemists