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of unmelted plumbago which might adhere to them I carefully rubbed them between my thumb and finger in the palm of my hand. I then placed them upon a fragment of wedgewood ware, floated in a dish of mercury, and slid over them a small jar of very pure oxygen gas, whose entire freedom from carbonic acid had been fully secured by washing it with solution of caustic soda, and by subsequently testing it with recently prepared lime-water; the globules were now exposed to the solar focus from the lens mentioned vol. v. p. 363. It was near noon, and the sky but very slightly dimmed by vapour; although they were in the focus for nearly half an hour, they did not melt, disappear, or alter their form; it appeared however, on examining the gas, that they had given up part of their substance to the oxygen, for carbonic acid was formed which gave a decided precipitate with lime-water. Indeed when we consider that these globules had been formed in a heat vastly more intense, than that of the solar focus, we could not reasonably expect to melt them in this manner, and they are of a cha racter so highly vitreous, that they must necessarily waste away very slowly, even when assailed by oxygen gas. In a long continued experiment, it is presumable, that they would be eventually dissipated, leaving only a residuum of iron. That they contain iron is manifest, from their being attracted by the magnet, and their colour is evidently owing to this metal. Plumbago, in its natural state, is not magnetic, but it readily becomes so by being strongly heated, although without fusion, and even the powder obtained from a black lead crucible after enduring a strong furnace heat, is magnetic. It would be interesting to know, whether the limpid globules are also magnetic, but this trial Ĭ have not yet made.

"I have already stated, that the white fume mentioned above, appears when points of charcoal are used. I have found that this matter collects in considerable quantities a little out of the focus of heat around the zinc pole, and occasionally exhibits the appearance of a frit of white enamel, or looks a little like pumice stone, only, it has the whiteness of porcelain, graduating however into light grey, and other shades, as it recedes from the intense heat. In a few instances I obtained upon the charcoal, when this substance terminated both poles, distinct, limpid spheres, and at other times they adhered to the frit like beads on a string. Had we not been encouraged by the remarkable facts already stated, it would appear very extravagant to ask whether this white frit and these limpid spheres could arise from carbon, volatilized in a white state even from charcoal itself, and condensed in a form analogous to the diamond. The rigorous and obvious experiments necessary to determine this question, it is not now practicable for me to make, and I must in the mean time admit the possibility that alkaline and earthy impurities may have contributed to the result. "In one instance contiguous to, but a little aside from the charcoal points, I obtained isolated dark-coloured globules of melted charcoal, analogous to those of plumbago.

"The opinion which I formerly stated as to the passage of a current from the copper to the zinc pole of the deflagrator, is in my view fully confirmed. Indeed, with the protection of green glasses, my eyes are sufficiently strong to enable me to look steadily at the flame, during the whole of an experiment, and I can distinctly observe matter in different forms passing to the zinc pole, and collecting there, just

as we see dust, or other small bodies driven along by a common wind; there is also an obvious tremor produced in the copper pole, when the instrument is in vigorous action, and we can perceive an evident vibration produced, as if by the impulse of an elastic fluid striking against the opposite pole.

"If, however, the opinion which you formerly suggested to me, and which is countenanced by many facts, that the poles of the deflagrator are reversed, the copper being positive and the zinc negative, be correct, the phænomena, as it regards the course of the current, will accord, perfectly well, with the received electrical hypothesis."

We must defer the succeeding articles until our next, for want of

room.

Y. Calculus of Cystic Oxide from a Dog; Constituents of that Substance, &c.

The following are M. Lassaigne's description and analysis of a caleulus extracted from the bladder of a dog, which he found in the collection of calculi belonging to M. Girard, Director of the Royal Veterinary College of Alfort.

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It weighed about 38 grains troy; was of a yellowish colour, semi-transparent, of an irregular form, glossy (lisse) on the surface, and confusedly crystallized throughout its substance; specific gravity, 1:577. It consisted of

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The oxalic acid could not be obtained in an uncombined state, but its existence was inferred from the property possessed by the residue of the calculus insoluble in potassa, of being partially converted into carbonate of lime by a slight calcination.

M. Lassaigne has examined the combinations of cystic oxide with potassa, and ammonia, and with the muriatic, nitric, sulphuric, phosphoric, and oxalic acids. The muriate, which is crystallized in acicular radii, consists of 5-3 acid and 94.7 oxide; the nitrate, crystallized in very slender needles, of 31 acid and 969 cystic oxide; the sulphate, a viscid uncrystallizable deliquescent substance, of 104 acid and 896 oxide, but M. Lassaigne suspects, that this compound had retained a portion of water; the oxalate, in efflorescent acicular crys tals, contains 22 oxalic acid, and 78 cystic oxide.

By means of ignition with peroxide of copper, M. Lassaigne has ascertained that the composition of cystic oxide is as follows:

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(Ann. de Chim. et de Phys. tom. xxiii. p. 328.)

VI. Inflammation of Gunpowder by the Heat of slacking Lime. To determine whether the heat given out during the slacking of lime was sufficient to fire gunpowder, a small quantity of it was put into a glass tube closed at one end; the tube was then placed in slack

ing lime and frequently removed, that it might acquire the exact temperature of the lime. Some minutes elapsed without any other effect being perceived than the volatilization of some of the sulphur of the powder, and it seemed as if no combustion would take place, but a loud explosion soon followed, without, however, breaking the tube.-(Ann. de Chim. et de Phys. tom. xxiii. p. 217.)

VII. Cleavage of Metallic Titanium.

Mr. W. Phillips has ascertained that the cubes of metallic titanium found in the slag of the iron-works at Merthyr Tydvil (see Annals, N. S. v. 67, and vi. 222), yield to mechanical division parallel to the planes of the cube.

VIII. Formation of a Meteorological Society.

We rejoice to state that efforts are making to establish a uniform and combined system of meteorological observation, by means of forming a Society for the purpose; the scheme has been highly approved of by several scientific gentlemen attached to Meteorology; and a meeting will be held on the third Wednesday in October, at the London Coffee House, Ludgate-hill, at eight o'clock in the evening, in order to take the subject into consideration.

ARTICLE XIV.

NEW SCIENTIFIC BOOKS.

PREPARING FOR PUBLICATION.

Mr. John Shaw, the author of the Manual of Anatomy, has in the press, a work on the Distortions and Deformities to which, from various Causes, the Human Body is subject.

A concise Description of the English Lakes, and the Mountains in their Vicinity, with Remarks on the Mineralogy and Geology of the District, by Mr. Jonathan Otley.

Mr. Cottle, of Bristol, will shortly publish Observations on the Oreston Caves, and on the Animal Remains contained in them.

JUST PUBLISHED.

Meteorological Essays and Observations; by J. F. Daniell, FRS. Description and Analysis of a New Sulphur Spring, at Harrogate; by W. West. From the Quarterly Journal of Science; with Additions by the Author.

No. 19 of G. B. Sowerby's Genera of Recent and Fossil Shells; containing the following genera:-Sigaretus, including Cryptostoma of Blainville; Stomatia, united to Stomatella; Pileolus, a new fossil Univalve, related to Nerita; Eburna, as distinguished from Buccinum spiratum and its congeners, which are usually united with it; Ranella; and Pholadomya, a new Genus of Bivalve Shells, of which a single recent Species has been lately found, but of which many fossil Species have been hitherto described as Carditæ, Lutrariæ, &c.

ARTICLE XV.

NEW PATENTS.

W. Wigston, of Derby, engineer, for certain improvements on steam-engines.—Aug. 11.

H. C. Jennings, Esq. of Devonshire-street, Marylebone, Middlesex, for an instrument or machine for preventing the improper escape of gas, and the danger and nuisance consequent thereon.-Aug. 14.

R. Rogers, of New Hampshire, in the United States of America, but now of Liverpool, Lancashire, master-mariner and ship-owner, for his improved lanyard for the shrouds and other rigging of ships and other vessels, and an apparatus for setting up the sanie.-Aug. 18.

J. Malam, of Wakefield, Yorkshire, engineer, for his mode of applying certain materials hitherto unused for that purpose, to the constructing of retorts and improvements in other parts of gas apparatus.-Aug. 18.

T. Leach, of Friday-street, London, merchant, but now residing at Litchfield, Staffordshire, for his improvements in certain parts of the machinery for roving, spinning, and doubling wool, cotton, silk, flax, and all other fibrous substances.-Aug. 18.

R. Higgins, of Norwich, shawl-manufacturer, for his improved method of consuming or destroying smoke.-Aug. 18.

G. Diggles, of College-street, Westminster, for his improved bit for riding horses, and in single and double harness.-Aug. 19.

E. Elwell, of Wednesbury Forge, Staffordshire, spade and edge tool maker, for certain improvements in the manufacture of spades and shovels. Aug. 20.

M. A. Robinson, of Red Lion-street, Middlesex, grocer, for certain improvements in the mode of preparing the vegetable matter commonly called pearl barley, and grits or groats made from the corns of barley and oats, by which material when so prepared, a superior mucilaginous beverage may be produced in a few minutes.-Aug. 20.

J. Goode, of Tottenham, Middlesex, engineer, for certain improve ments in machinery, tools, or apparatus, for boring the earth for the purpose of obtaining and raising water.-Aug. 20.

B. Rotch, Esq. of Furnival's Inn, London, for his improved lid for the upper masts of ships and other vessels.-Aug. 21.

J. Surrey, of Battersea, Surrey, miller, for his method of applying heat for producing steam and for various other purposes, whereby the expense of fuel will be lessened.-Sept. 4.

W. Woodman, of York Barracks, veterinary surgeon of the 2d Dragoon Guards, for his improved horse's shoe, which he denominates the beveled heeled expanding shoe.-Sept. 11.

B. Donkin, of Great Surrey-street, Surrey, engineer, for his discovery or invention on the means or process of destroying or removing the fibres from the thread, whether of flax, cotton, silk, or any other fibrous substance composing the fabrics usually termed lace net, or any other denomination of fabric, where holes or interstices are formed by such thread in any of the aforesaid fabrics.-Sept. 11.

[merged small][merged small][graphic][subsumed][merged small][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][ocr errors][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed]

The observations in each line of the table apply to a period of twenty-four hours, beginning at 9 A. M. on the day indicated in the first column. A dash denotes that the result is included in the next following observation.

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