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of a little chalk to the must of grapes, when it is somewhat sour ; for the acidity being due to citric and tartaric acids, there is thus formed a precipitate of citrate and tartrate of lime, while the must becomes sweeter, and yields a much finer wine. Too much chalk may render the wine insipid, since it is proper to leave a little excess of acid in the must. He concentrates his must by boiling, and adds the proper quantity of chalk to the liquor, while it is still hot. Even acid wine may be benefited by the addition of chalk. Oyster-shells, we believe, bave been frequently used with this view; and calcined oyster-shells are a cleaner carbonate of lime than common chalk.

Test for Magnesia.-- In the Annales de Chimie for May last, it is stated, that if we spread any clear liquid upon a plate of glass, and then trace the word Magnesia upon the glass so covered, with the end of a glass rod, that word will appear in white characters if magnesia be present in the solution ; if not, no such appearance will result.

Green Fire.-In a former number of this Journal we presented our pyrotechnical readers with a recipe for the red fire which has lately gained so much celebrity in the theatrical representations of confiagrations, and which forms so beautiful a change in fireworks. We now give them the component parts of a more modern invention, which has long been a desideratum in this branch of art, namely, a green fire, and which, when burned in a reflector, sheds a beautiful green light upon all surrounding objects ; it may also be employed in the changes of fireworks alternating with red and blue fire. Take of Flowers of sulphur

13 parts Nitrate of baryta

77 Oxymuriate of potassa

5 Metallic arsenic

2 Charcoal

3 The nitrate of baryta should be well dried and powdered ; it should then be mixed with the other ingredients, all finely pulverized, and the whole triturated until perfectly blended together. A little calamine may be occasionally added, in order to make the compound slower of combustion ; and it is above all things requisite, that both in this and the red fire the trituration of the materials should be continued until they are completely mixed.

Effect of Voltaic Electricity upon Alcohol.-M. Lindersdorff produced an ethereal fluid by the action of the voltaic pile upon alcohol ; and by continued electrization, a mixture of equal parts of alcohol and liquid ammonia lost its inflammability, and acquired a bitter flavour, yellow colour, and nauseous odour. On evaporation it left a

These are very interesting results.

Considerations on the existence and state of Sulphur in Vegetables.M. Planche suspended a piece of rag, impregnated with acetate of lead, and also a plate of clean copper, within the capital of an alem, bic in which he was drawing off distilled waters from plants, and found that the above re-agents were powerfully acted on, as if they

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greasy residue.

had been exposed to a stream of sulphuretted hydrogen. He found, moreover, that water and sulphur boiled together, as also roll sulphur heated, without the addition of water, evolved sulphuretted hydrogen; and from the two latter experiments he infers, that in plants the sulphur is in its simple state.

According to MM. Thibierge and Robiquet, the oil of mustard contains a pretty large quantity of sulphur; and from some comparative trials, it seems there to be in the state of sulphuretted hydrogen. In fact, distilled water, saturated with the essential oil of mustard, blackens the solution of nitrate of silver. Oil of caraways absorbs a very large quantity of sulphuretted hydrogen gas, when it is passed through it; and assumes, in consequence, a very fetid odour. He supposes that the sulphur which exists as such in the mustard-seed, is converted into sulphuretted hydrogen during distillation with water, and in this state unites to the oil. A portion of the sulphur is deposited at the end of some days. The following plants yielded much sulphur: the flowers of the elder, linden, and orange-tree; the whole plant of pellitory and mercury; the flowering tops of hyssop, melilot, tarragon, and rue; the seeds of dill, caraway, cummin, and fennel; and clove-buds.

Detection of Poisons.-A paragraph has appeared in the papers, recommending blue sugar-loaf paper as a test of distinction between oxalic acid and Epsom salt; it is reddened by the former, but not affected by the latter. This is perfectly true; but a simpler test consists in wetting the tip of the finger, applying it first to the supposed salt, and then to the tongue-if oxalic acid, it tastes very sour; if Epsom salt, very bitter and saline.

Many restrictions have been suggested upon the sale of arsenic; the only effectual bar to the mischief that results from it, is prohibition. It is of no use in medicine, and should therefore be rejected. from the pharmacopoeia. Apothecaries and druggists need not then keep it. It is sometimes employed as an instrument of research, in the chemical laboratory, which might be sufficiently supplied through

other channels.

Bezoars voided by a Woman.-The calculi called bezoars are found in the stomach and intestines of certain herbivorous animals, but had not been met with in those either of carnivorous animals or of man, until Dr. Champion, an eminent physician of Bar-le-duc, sent some for analysis to M. Henri Braconnot, which had frequently been voided, in a diurnal vomiting of blood, by an unmarried woman, whose menstruation was irregular, and whose urine had become much diminished in quantity before the evacuation of these concretions commenced.

These bezoars have the form of crisp almonds (pralines) and are as large as small hazel nuts; their surface is tubercular and coloured brownish red by the blood. Internally they are of a yellowish white, inclining to fallow, and appear to consist of brilliant crystalline grains; they do not present any concentric layers. They are usually of a close texture, but are sometimes cellular, like the marrow of bones; and may be cut with a knife like wood, of which they have also the aspect. At one of their extremities there is an infundibuliform deVOL. I. No. 6.-Museum. 4 C

pression, often filled with dried blood, which communicates with a tube extending throughout their length; this tube being sometimes partially or even wholly filled up. Two of them had cavities in the interior, like little geodes, but none offered a distinct nucleus; their specific gravity was above that of water.

Electro-Magnetic Eperiment.-M. Nordenskiold, of Abo, now in this country, has communicated to me, the following curious and simple experiment of Dr. Seebeck, of Berlin.-Take a bar of antimony about eight inches long, and half an inch square, connect its extremities by twisting a piece of brass wire round them so as to form a loop, each end of the bar having several coils of the wire. If one of the extremities be heated for a short time with a spirit lamp, electro-magnetic phenomena may be exhibited in every part of it.

Royal Academy of Sciences in Paris.-July 1. A report was made on a curious fact of vegetable physiology communicated by M. D'Hombres-Firmas. Vegetables, except a small number, and especially trees, do not flower or bear fruit till after a certain growth; and the leafing precedes the flowering. The observation communicated relates to two fine bunches of lilac, on the ground, which M. Villaret took at first sight for bunches detached from a neighbouring tree, and planted in the ground by children, but which he found to be rooted. The reporter considers the fact as very important.

July 15. M. Cuvier delivered a highly favourable report in the name of a commission upon the memoir of M. Fleureus, entitled "Researches relative to Sensibility and Irritability." The object of these researches has been to ascertain by a series of experiments, whether the sensitive and the motive powers reside in the whole nervous system, or each in distinct parts of it. And the interesting result appears to be, that in the nervous system there are two proper ties essentially distinct: the one, to excite muscular contractions; the other to receive impressions. It has been the object of M. Fleureus to discover, by isolating and detaching the several parts of the brain and nervous system, in which of them these properties severally reside.

M. Cordier has been nominated to fill the place left vacant in the Sections of Mineralogy by the lamented death of M. Hauy; and M. Brougniart has been elected to succeed him as Professor at the Mu

seum.

Linnean Society of Paris.-M. Viellot gave an account of an eagle never yet described, killed in the Forest of Fontainbleau, and which he proposes to call Aquila fasciata.

Wool employed in the Manufactures of France.-" Formerly, and even to the present time, the clothiers sought out for long and sound wools, in the expectation of finding in them, proportionally less of grease and foreign matter, and more freedom in the staple, but also with a view of giving more strength and firmness to their cloths. The very reverse now takes place. In order to maintain a competition with the cloths of England, they require only such wools as are short, weak, and silky: and they manufacture only fine and slight

cloth, soft and silky, which will'scarcely last so long as the transient taste which has given rise to them.

"This predilection has produced a change in our flocks; and the grower of the raw material, who seeks for a ready sale, has been compelled to conform to the desires of the manufacturers and the depraved taste of the consumer. In order to diminish the length of their wool, they have been tempted to shear their sheep twice in the year, allowing seven months for the first growth and five for the second: but, besides that, it is only a small number which is capable of yielding twice in the year a wool of sufficient length; the prospect of reaping advantage from animals twice in the year, submitted to the shears, seems more than doubtful. The experiments made by M. Bourgeois, on his estate at Rambouillet, leave no doubt on this subject."

If the above facts (taken from the Bibliotheque Physico-Economique) are to be depended upon, they are worthy the attention of the English clothier, who will perceive that the French clothier has had recourse to a change in the wools consumed in his manufacture, with a professed view of maintaining a rivalry with English cloth.

On preserving Fish by Sugar. In a letter to Dr. BREWSTER from J. MAC CULLOCH, M.D. F.R.S, &c. Communicated by the Author. DEAR SIR,

As you have not scorned to give your readers a useful notice respecting the preservation of meat by the use of vinegar, you may possibly not refuse to add to it some remarks on the curing of fish by means of sugar. This is a very antiseptic substance, as is well known; and though partially employed in hams, it is scarcely considered, as what it really is, one of the most active substances in their preservation, being rather employed blindly, and with the notion of giving flavour. It is highly deserving of a much more extended trial, particularly the curing of meat for the Navy; as it does not, like salt, destroy the provisions, and as it is in itself nutritious.

But to return to the subject of this notice: Fish may be preserved in a dry state, and perfectly fresh, by means of sugar alone, and even with a very small quantity of it. I have thus kept salmon, whitings, and cod, for an indefinite time, and with the best effect; an experiment which I was led to try in voyaging among the Western Islands, where matters of this nature are often of considerable moment.

Fresh fish may thus be kept in that state for some days, (but I know not how long,) so as to be as good when boiled as if just caught. If dried and kept free from mouldiness, there seems no limit to their preservation; and they are much better in this way than when salted. The sugar gives no disagreeable taste.

This process is particularly valuable in making what is called Kippered Salmon; and the fish preserved in this manner are far superior in quality and flavour to those which are salted or smoked. If desired, as much salt may be used as to give the taste that may be required; but this substance does not conduce to their preservation.

In the preparation, it is bar ely necessary to open the fish, and to apply the sugar to the muscular part, placing it in a horizontal position for two or three days, that this substance may penetrate. After this

it may be dried; and it is only further necessary to wipe and ventilate it occasionally to prevent mouldiness.

A table spoonful of brown sugar is sufficient in this manner, for a salmon of five or six pounds weight; and if salt is desired, a tea spoonful or more may be added. Saltpetre may be used instead, in the same proportion, if it is desired to make the kipper hard.

In his "Memoir on the fall of Leaves," M. Vaucher objects to the hypothesis that attributes the fall of the old leaf to the growth of the new bud; to that also which ascribes it to an alleged superabundance of juice in the plant, and defective transpiration; or to the inequality of growth between the circumference of the stem and the petiole of the leaf. The true cause, he supposes to consist in a peculiar structure that obtains at the insertion of the petiole with the stem. The fibres of the petiole, instead of being a simple prolongation of those of the stem, are, according to him, distinct from them. At the point where the separation of the leaf occurs, there is only a sort of approximation, or soldering, and not a real continuity of vessels. This soldering is supposed to be produced by the interposition of parenchyme between the two systems of vessels. As long as this parenchyme is supplied with juices, and retains its vegetative power, the adherence of the petiole is maintained; but when it begins to dry, the connexion fails, and the leaf falls.

As this hypothesis is made to rest on anatomical grounds, we could have wished that M. Vaucher had exhibited something like a demonstration of the structure of these parts. He mentions, indeed, the existence of a circular ring or rising, visible exteriorly, at the place of junction of the petiole with the branch; but that this is caused by the interposition of cellular tissue between the vessels of the stem and petiole, or by any sort of soldering of the extremities of these vessels with one another, we have no evidence. We incline rather to the old opinion, that these vessels are truly continuous; and consequently, that whatever be the cause of the fall, it is accompanied by a rupture of vessels. That a diminution or cessation of vegetative power in the part precedes this event, has been generally deemed probable; though others, as M. Vrolick and Sir J. Smith, consider the fall of leaves in autumn as a sloughing of worn-out parts, effected by the vital energy of the parts in contact with them.

Curious appearance observed on the Moon at the Cape.- The Reverend Fearon Fallows, the astronomer at the new observatory erected at the Cape of Good Hope, observed with his naked eye a whitish spot on the dark part of the moon's limb. This happened on the 28th November, 1821, about 8 o'clock, P.M., when the moon was shining with a brilliancy which he had never observed in England. This spot seemed now and then to flash with considerable lustre. With an achromatic telescope about 4 feet long, magnifying 100 times, the spot seemed like a star of the sixth magnitude, and there were three others much smaller, but one of these was more brilliant than the one he had seen with the naked eye. The largest spot was surrounded by a nebulous appearance, but nothing of this kind was observed about the small brilliant spot. The two others were similar to faint nebulæ, increasing in intensity towards the middle, but without any defined luminous

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