Imágenes de páginas

as A, B, in the annexed figure.

when the flow is uniform, and at when the river is rising, this s, as A, C, B; and, that on the

concave, as A, D, B, when the

ifferences of opinion which exist y be principally owing to one or been observed, and erroneously It used in these experiments on 1, an accurate account of which of publication, and of comparison

the same object, and which will

Rocky Strata. satisfactorily ascertained that a mperature of the schistose and severally examined at the same emperature belongs.

isured. abundantly in proportion to the

impinges, was confirmed by the ese philosophers did not proceed lar case, of the incident, to the ty of cases in which, the property

that its quantity was variable, it eful, to be able to ascertain the articular body and surface. M. f an apparatus, designed by him, acy. Another instance in which site delicacy and sensibility of his perties and proportions of this ed a short time ago to lie far

at in the Open Air. xford, on the 6th of November ne Bromelia pinguis, a native of in the open air in the garden of on-upon-Stour. This plant has s, although a drawing of it in

flower is given in the Hortus Elthamensis ; and the individual plant alluded to had been tried first in the pinery, and afterwards in the greenhouse, but had never put forth flowers, till it was taken out of doors, when it flowered, though the petals never properly expanded.

Phosphoric Light emitted by Flowers. At the same meeting, a communication was also read by him respecting an electrical phenomenon, which occurred in the garden of the Duke of Buckingham, at Stowe. On the evening of Friday, the 4th of September, 1835, during a storm of thunder and lightning, accompanied by heavy rain, the leaves of the flower called @nothera macrocarpa, a bed of which is in the garden, immediately opposite the windows of the manuscript library at Stowe, were observed to be brilliantly illuminated by phosphoric light. During the intervals of the flashes of lightning, the night was exceedingly dark, and nothing else could be distinguished in the gloom except the bright light upon the leaves of these flowers. The luminous appearance continued uninterruptedly for a considerable length of time : it did not appear to resemble any electric effect: and the opinion which seemed most probable was, that the plant, like many known instances, has a power of absorbing light, and giving it out under peculiar circumstances.

Beet-root Sugar. The exertions making in France and throughout Germany to simplify the process of preparing sugar from the Beet are immense and unceasing. At the recent meeting of the German naturalists, at Bonn, the section of Agriculture and Rural Economy was almost entirely occupied with papers and discussions on the subject. At Valenciennes, a manufacturer has succeeded in discovering a method of crystallizing the whole of the saccharine® matter of the Beet without producing molasses in the process. Three sugar-houses there have adopted the new plan.

Science assisted by the State. The French government, in October last, being about to despatch a vessel, La Bonite, to the Brazils and Sandwich Islands, through the Chinese and Indian Seas, gave permission to the Academy of Sciences of Paris, to take advantage of the circumstance for scientific inquiry. This body eagerly embraced the offer, and appointed M. Arago, and other tinguished members, to draw up suitable instructions for the officers of the vessel ; these gentlemen are also stated to be able and willing to second the views of the academy. Instruments, such as the shortness of the time would permit, were immediately collected and prepared. Should not this example stimulate us to seize some of the many hundred opportunities which occur every year in this country, not only in the case of the government, but of the numerous public bodies, companies, and powerful individuals, who are daily sending out vessels to cross every sea, an! visit every point of the globe? It is true, we cannot be accused of absolute neglect,—there are a few valuable instances to the contrary; but how rarely do we see a case in which our Royal Society is occupied as the French Academy has lately been !

In the present instance, gratifying and important results have occurred even before the sailing of the vessel, as is proved by the following fact. During the examination and comparison of some of the instruments intended to be sent on board La Bonite, some extraordinary irregularities were observed in the direction of the magnetic needle. These happened on the 17th, 18th, and 19th of November. The observers were led to suspect the existence of an Aurora Borealis, but the atmosphere at Paris was cloudy and unfavourable for ascertaining it. In a few days the correctness of the supposition was made evident, and the extensive influence of a remote Aurora upon the magnetic needle was confirmed, by the arrival of the English newspapers, and also of a communication from Nismes, containing descriptions of a brilliant Aurora, which occurred in the night of the 18th of November*. We have little doubt, but that this series of beneficial effects will be continued, and that, barring accidents, the return of La Bonite will, in addition to the discharge of her duties to the French government, be accompanied by a gratifying accumulation of knowledge to the French Academy, and through them to the scientific men of all nations, and eventually to the world.

New Electro-Chemical Apparatus. M. BECQUEREL of Paris, has introduced to the notice of the scientific world, a modification of the Electro-chemical Battery, which reduces it to a striking simplicity. And yet he finds that all bodies exposed to it are either decomposed or attacked, exactly as if they were submitted to the Voltaic pile; that its power of action continues uninterruptedly; and that the intensity of its current is not affected, in any appreciable quantity, by the causes which tend to weaken the electro-chemical effects of the pile.

Simple as M. Becquerel's apparatus is, its arrangement has already been improved by M. Aimé, who describes the newer instrument as follows:-A U-formed tube, pierced with a small hole at its lowest part, is to have its legs half-filled with very fine sand. One of the legs is then to be filled up with diluted sulphuric acid, and the other with a concentrated solution of sea-salt. The two fluids will descend through the sand, and combine at the lower part of the tube. As soon as this combination is effected, the fluid, resulting from the combination, escapes immediately through the hole, which is loosely plugged with a bit of asbestos to prevent the escape of the sand. A slip of platina is dipped into each leg, and wires from these slips connect them with a galvanometer. On making contact, the needle immediately indicates, by the change in its direction, the formation of the current produced by the action of the two fluids on each other. The intensity of this current varies with the degree of concentration of the solutions, and with the rate at which the combination is made; to facilitate the latter, the size of the hole may be increased.

When a constant and regulated supply of the solutions, and a proportionate discharge of them, after they are combined, are obtained ; the process can be carried on for any desired period without intermission. There is, however, one precaution necessary,—the solutions must be so prepared and proportioned, that they shall not, on combining, form a salt and obstruct the discharge. From the experiments of M. Becquerel and M. Aimé there seems already ground for believing, that electro-chemical currents of determined intensity may be produced and maintained during whatever time may be necessary to effect chemical decomposition, by this powerful agent.

Duration of Life in France. In a recent memoir by M. Demonferrand, he states, that the average length of human life in France is 33 years, 8 months, and 11 days.

* See Notice of the Aurora Borealis, at Oxford, p. 65.

Magnetism as a Motive Power. The Rev. Mr. M'Gauley exhibited to the British Association at Dublin, a very simple contrivance hy which Magnetic force is employed to drive machinery. The magnetism is produced in soft iron by a galvanic battery; and by an ingenious but simple contrivance the connexion of the wires is alternately reversed, so that a bar of iron is kept continually moved backwards and forwards between the opposing poles. This moves a crank, which turns a wheel, to which of course any other wheels can be attached. The extent of power he conceives will be as unlimited as the strength of the battery which is used.

Marine Instrument. ONE of the instruments furnished by the French Academy to the officers of La Bonite, is intended to procure specimens of sea-water at great depths. M. Biot formerly used an instrument of this nature in the Mediterranean, and obtained sea-water from a depth of about 450 fathoms, together with all the air, &c., that it might contain, for the purpose of examining and comparing it. M. Savart, who has superintended the execution of the new instrument, has introduced some important improvements. We hope to be able to give a description of these improvements from the author himself.

Simplification in the Laws of Chemical Action. M. Biot, at a sitting of the Academy of Sciences, on the 23rd of November last, opened a sealed communication which he had deposited with the Academy for some time, and read from it an interesting paper, in which he had applied optical principles most successfully to the resolution of the constituent proportions of chemical combination. At the conclusion, he called the attention of his auditory to the extreme simplicity of the new laws he had placed before them; and observed, that he felt justified in thinking that it was probably not so difficult as it is at present imagined, to reduce the phenomena of chemistry to the same simple and exact calculation as those of mechanics.

Convenient Chemical Thermometer. Mr. PASTORELLI, of Cross-Street, London, and Herr Greiner, of Berlin, have

simultaneously succeeded in producing an improvement in the thermometer for chemical purposes. The preservation of the scale from the action of acids, and the safety with which the bulb and tube may be used as a stirrer and afterwards cleaned from any viscous or other matter into which it may have been dipped, are accomplished without any diminution of the sensibility of its action. The accompanying figure shows the improvement. The tube of the thermometer is passed up a glass cylinder, of a diameter rather less than that of the bulb; the cylinder can therefore rest upon the bulb, as at A, and is here attached to it by the blow-pipe. The scale is inserted within the cylinder; and the brass cap which terminates it, preserves the tube in its axis. The idea of this arrangement and guard is by no means new, and many thermometer-makers have attempted it, but they never were able to make the joint at A to

stand the necessary variations of temperature. Mr. Pastorelli, after a number of experiments made during eighteen years, has at length succeeded, and will guarantee these thermometers through all the usual ranges.


Grand geodæsical Operations in India. It will be gratifying to the lovers of science to learn that a trigonometrical survey of India is carrying on by the munificence of the East India Company, and is to proceed with increased rapidity. No less than fifty-six theodolites have been prepared by one of the first makers in London, and sent out within the last two months. Major Everest, Surveyor-General of India, is also continuing the measurement in that country of an arc of the meridian of an enormous extent. This is using the “giant's power" for noble purposes !

Income of the Dublin and Kingstown Railway. The first working year of this railway ended on the 16th of December last. The total receipts were 31,0661. 85. 6d.; the number of passengers, exclusive of annual subscribers, 1,068,018; number of trips made by the loco-motive engines, 22,050; number of miles travelled, 125,275.

Two small Cabinet Figures in white Carrara Marble ARE at present deposited at the Adelaide-Street Gallery, with a view to sale. These chefs d'æuvres of modern sculpture formerly belonged to the unfortunate Queen of France, Marie Antoinette; they ornamented her saloon at Trianon, and were rescued from the destructive fury of the French revolution, by an Austrian nobleman, and carried to his palace near Vienna ; where, during the Congress in 1814, they excited the admiration of the Allied Sovereigns. An offer of two thousand guineas was made for them by the late Marquis of Londonderry, then Lord Castlereagh, and Sir Thomas Lawrence, but this extravagant sum was refused by their owner, then at the very pinnacle of grandeur and prosperity. They remained in his possession until within the last few months; when from the most calamitous reverses of fortune, the consequence of a misplaced confidence in the present ex-King of France, he has been compelled to consign them to the care of a friend, whose only difficulty in disposing of them would, we apprehend, arise from the magnitude of the price asked,- fifteen hundred guineas.

The first represents Venus as having just risen out of the ocean, and in the attitude of wringing out her hair. Whether we consider the graceful and expressive disposition of the tout ensemble, or, wishing to fix on any one part as more worthy of admiration than another, select the contour of the back, and the remarkable truth and elegance displayed in the action of the arms and hands-we are bound to admit, it presents so close and classical a resemblance to the antique as might deceive the most skilful artist, but that the features are those of the amiable Madame Elizabeth of France, sister to Louis the Sixteenth. The other figure is also that of a Venus seated in a large conch shell, and gliding as it were along the surface of the waters; she is drawn by two Tritons and supported by Cupids; the countenance of this figure is a portrait of the fascinating Queen herself, sculptured at the very time when, as

never lighted on this orb, which she hardly seemed to touch, a more delighftul vision." This, like the former statue, is devoid of drapery. The position of the body, and the disposition and action of the limbs, evince at once the most perfect anatomical proportion, and the most easy and graceful arrangement. The elaborate workmanship displayed in the minuter parts and accessories is highly deserving of attention in both the sculptures; but, perhaps, in the last mentioned the most indisputable evidence of the hand of the master is to be seen in the exquisite manner in which the bending of the body is effected.

Burke says

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