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LMOST all the inventions of the ancients owed their existence to to chance; but the discoveries of the moderns are rather the fruit of reflexion, and of the multiplied efforts of scientific men to apply their knowledge to useful objects. Let us pass in review the principal results of this direction.

The employment of combustible gas for illumination makes rapid progress in England, but this fine discovery has not yet received the same developement in Germany.

The lighting with gas, would make a far more rapid progress, if the discovery of Taylor should be confirmed. According to this discovery, combustible gas is procured by causing oil to fall drop by drop into a tube heated red hot, and which is kept in that state. The gas passes immediately from the tube to the lamp, and produces a beautiful flame, without any smell.

Sir H. Davy has increased his celebrity by the invention of his Safety Lamp, which secures the miners from causing explosions, which are so dangerous in places under ground. When the lamps of the workmen are surrounded by a very fine metallic gauze, the air alone penetrates and not the flame.

The same invention has suggested to the instrument-maker, Newman, his blow-pipe, with a mixture of hydrogen and oxygen gas. This contrivance has much more effect in the fusion of bodies, more or less refractory, than the blowpipe with oxygen gas alone, which had till now been employed to produce the greatest degrees of heat. Not only the metals which are the most difficult to melt, but diamonds, and other bodies hitherto reputed infusible, melt in a very thin current of explosive gas.

Sir H. Davy also discovered last year a means to procure permanent light without flame: he has taught us that a platina wire of sufficient fineness, and an inch, or an inch and a half long, which has been heated red hot, may be

long preserved in this state over a vessel in which there is sulphuric ether or alcohol, in a state of evaporation. Thus this incandescent wire may be employed as a cheap night lamp, or instead of a steel to light tinder.

The chemical apparatus for producing instantaneous ignition, which became rapidly in vogue, followed some years back the series of electric, galvanic, pneumatic, and phosphoric apparatus of the same kind. These chemical apparatus were founded on the experience that hyper-oxymuriate of soda, brought into contact with a combustible body (wood for instance), which has been plunged into sulphuric acid, sets fire to this combustible. Latterly this apparatus, which has become very common in Germany, has been rendered more convenient and less dangerous, by putting into the phial, instead of liquid sulphureous acid, very fine sand, asbestos, gypsum, or some other body, which the acid does not destroy, and which is moistened with it. Several thousand matches may be lighted in this manner before it is necessary to renew this kind of indissoluble sponge, which is to produce the inflammation.

Platina had long been employed for various purposes; and as it experiences but little action from the substances which may exercise some influence over it; as it is not brittle; as it bears a great degree of heat without melting; lastly, as it is very dense, &c.; it had been used for various vessels, crucibles, some works of the mechanic arts, for trinkets, &c.; but new and more perfect_methods have been lately invented in France, as well as in Germany, to melt this metal with more facility, to purify it, and to render it more easily worked. They have even gone so far as to platinate vases, porcelain, &c. in the same manner as they gild and silver them.

Janetty at Paris, Frick at Berlin, and Leithner at Vienna, have made very successful experiments in this way. The From the German of M. Poppe, of Tubingen.

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employment of platina to line the pans and touch-holes of fire-arms, may be very useful; the arms can no more be injured by ac ds, and gain much both in safety and durability.

The manner of working zinc has been greatly improved ; and the employment of this metal to sheath ships, to cover houses, for the manufacture of common candlesticks, for organ pipes, &c., seems to be gradually becoming more general. It is probable that the manufacture of white zinc, instead of white lead, may be successful. Some use may, perhaps, be found also for the new metal called Cadmium, discovered by Professor Stromeyer of Gottingen, in the blende (sulphuret) of zinc.

M. Gerlach of Vienna has manufactured two kinds of cast steel of remarkable goodness, one of which is susceptible of being welded to iron. M. Fischer of Schaffhausen, bas also obtained in his manufactory, varieties of steel, which are very valuable for their different qualities. The English cast-iron is so soft that it is made into nails without forging. Mr. Schafzahl of Gratz has even succeeded in manufacturing iron nails, without employing fire in any part of the process, from the bar iron to the smallest nail. All is done by the action of machines; twenty of which make annually as many millions of nails. M. Dufand, a Frenchman, was the first who discovered that cast iron reheated, may be sawn as easily, and in the same time, as dry wood of the same bulk.

The shoes without seams, and fastened with nails, invented some years ago in America, and imitated in England, in the manufacture of which a single machine to cut, press, and nail the leather, enables one workman to make several pair in a day, are now manu. factured also in some parts of Germany, especially in Bavaria and Thuringia.*

There have lately been erected in England, and in America, iron wire

* M. Brunel, the ingenious inventor of the machine for making shoes, has, we understand,

ceased to use it, since peace has lessened the demand for shoes for the army.

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bridges, which are very light, convenient, and cheap, and some of them four hundred feet in length.

Many able mechanicians have been endeavouring to discover a perpetuum mobile; but many, who thought themselves on the point of succeeding, found their hopes deceived, and the phantom they had pursued eluded their grasp. The clock of M. Geiser, an admirable piece of mechanism, seemed to have solved this great problem, in an ingenious and simple manner: but it deceived only for a time, not only the author of this Essay, but many of the most excellent mathematicians for in this clock springs were concealed in the most artful manner, which were wound up at certain times, to aid the apparent power, which was not able alone to keep the machine in motion. Above a year ago, the author of this article discovered this trick, with several other lovers of the arts, who had joined with him to examine the machine; and he soon after made his discovery public.

The column of Zamboni, and the clock connected with it, by that artist at Verona, which have now gone without interruption for above four years, as well as that of Ramis at Munich (called the electric pendulum clock), are, therefore, perhaps, the best perpetuum mobile that we yet have. By this name we of course understand a machine, which is able constantly to renew the cause of its motion by its own mechanism, and whose moving principle preserves its action without interruption, and without any new impulse, till it is stopped either by the wear of the machine, or by violence. The invention of a machine possessed of this property is indeed very difficult, but not impossible, as Kastner, Langsdorff, and other mathematicians have demonstrated.

Far more solid advantages were afforded by the Press of Real, or hydrostatic press, destined chiefly for the preparation of extracts from fruits or plants, as the hydromechanic press of Bramah and William is to press cloth and paper, to extract oil from seeds, malt, &c. These presses have been introduced with great effect in Germany, and with

many essential improvements, especially by M. Nathusius at Neu-Haldensleben, in the duchy of Magdeburg, where they have even been employed to pull up trees, and draw piles out of the water.

M. Hoffmann at Leipsig, has invented an aerostatic press, in which the pressure and the filtration are not effected, as in that of Real, by the action of a high column of water, but by means of a compression pump. A still more interesting aerostatic press has been invented by Dr. Rommershausen, at Acken on the Elbe. The effect of this press depends upon the great pressure of the atmosphere on the sides of a vessel from which the air has been evacuated. A recipient which may be submitted to the action of the air pump, is furnished with a diaphragm, or partition, on which is placed a filter, and under this a vessel proper to receive the liquid, which has been put above the filter. When the vacuum is made, the pressure of the external air forces the liquid through the filter, and contributes to the more complete and rapid extraction of the soluble parts.

The new brewing apparatus of the Englishman Nordham, on account of the saving of time, labour, and fuel, and the good and strong beer which it makes, is much approved in Germany. The apparatus for the evaporisation and distillation of ardent spirits, have been lately brought to a much greater degree of perfection, and we obtain very easily, with a great saving of time and fuel, by a simple distillation, very good brandy, and from this brandy highly rectified spirit of wine, without running the risk of burning it, or of throwing off the head of the still. The disengaged vapours spread themselves through subdivided reservoirs, and deposit their aqueous particles, so that only the most volatile may be condensed in the worm, and thence pass into the recipient. Tutte of Berlin, first shewed with what success rarefied air might be applied to distillation; he contrived an apparatus accordingly, which has produced a very favourable result.

The idea of separating slate by the congelation of water in the quarries, is very curious. The rain water being let

into the crevices of the blocks, when it freezes, its expansion suddenly separates the layer.

The discovery made by Varnhagen, a German, at Rio Janeiro, is still more important. He has found that sawdust, particularly of soft wood, mixed with gunpowder, triples its force. The method of applying this discovery to the blowing up of rocks is peculiarly interesting. The mine is charged with a mixture of saw-dust and powder, and the whole covered with dry sand, thro' which is passed a reed or straw filled with priming powder, so that the danger resulting from the dispersion of the stones is prevented.

The application of steam to the purposes of cooking, heating rooms, drying, &c. not only continues, but becomes more and more extensive. Querner, Meissner, Dingler, Salzer, and other ingenious men, continue successfully to improve their steam-kitchens and other useful steam apparatus. boats introduced into several parts of Germany, as on the Elbe for instance, are still constantly employed, but the steam carriages are neglected.

The steam

Great improvements have been made in all parts of wheel-carriages; to the new springs of Mr. Edgeworth in Ireland, and of Reichenbach, at Munich ; to the felloes of one piece of the Prussian captain, Neander, the safety drag of the Englishman, Busch; the contrivance of Bruggemann in Hamburg, which prevents all danger from horses running away with a carriage; and to the moveable axle-trees of Lankensperger of Munich, may be added M. Yelin's (of Munich) contrivance for clogging a wheel, and Mr. Padbury's for preventing the wheels from flying off. The well known Draisiennes, or Velocipedes, (invented by M. Drais, in Manheim) which have been both too much extolled and too much depreciated, have been much improved both in lightness and convenience by many artists; particularly Bauer of Nuremberg, and Wollenschlager of Francfort. The self-moving carriages, as they are called, namely, that of Kittlinger in Schwalbach, have hitherto had as little success as the machines that have been invented

discoveries, a great number of others, some ingenious, some useful, and others combining both species of merit, such as Ranson's micrometer compass, Uhlhorn's instrument for measuring velocities, Mander's lactometer, Douglas's instrument for discharging cannon without a match, Repsold's reflector for light-houses,Bowler's new butter-churn,

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the stone paper, (instead of stone) for the purposes of lithography, and several others, it would be difficult to find in the history of the arts, any period in which so many really useful inventions have been produced within so few years, as in the beginning of the nineteenth century.

USINA is only remarkable as a place of embarkation on the Lagune. Several English carriages were put up here whilst the owners were occupied at Venice. The city from this station presents a remarkable and superb appearance, rising as from the waters, and crowned with pinnacles, domes, and spires. We entered by the Grand Canal, and landed near the famous Rialto, composed of a single arch thrown over it; but however beautiful it may appear to the Venetians, we thought it trifling, when compared with the graceful proportions of the Blackfriars and Waterloo Bridges to our own capital. We ascended the tower of St. Mark, in order to obtain a general idea of this metropolis; its height is not extraordinary, but from the flatness of the surrounding scenery it gives the spectator an advantageous view of the city, its port and shipping, and the windings of the neighbouring coasts. One side of this celebrated square was designed by Palladio, and is characterised by the richest architectural ornaments: it affords a principal promenade in the evenings, and when fully lighted has a brilliant appearance; the ground floors are occupied chiefly by caffés,and the shops of jewellers, in which gold chains are sold by weight, and vary in price according to the value of bullion. The church of St. Mark, which occupies one side of the square, was constructed on the model of Santa Sophia at Constantinople; if a correct copy, the taste of the original must have been defective; the interior has a gloomy appearance, but it boasts of large designs in mosaic over

the domes, &c.: the floor, which undulates like the waves of the sea, is ornamented in the same manner: the exterior is decorated with five domes and numerous statues, and its walls are painted in fresco, but the general outline is heavy. The famous bronze horses supposed to have been the workmanship of Lysippus surmount the portico. In the library, formerly the council-room, are portraits of the Doges, and paintings representing the sieges and reduction of Constantinople by the Venetians, and on the ceiling a beautiful design of the civic genius crowned by Fame; this last is from the pencil of Paul Veronese. Here is also a marble bust of the Emperor of Austria, and a sculpture of Ganymede borne aloft by the eagle. The present council-room, with its anti-chamber, are ornamented by the same painter. Proceeding to the palace, we were shewn in the first room a veiled statue of Coradini, similar to that of Pudor at Naples: in the third, paintings of Lucretia stabbing herself, by Guido Cagnacci, and Moses striking the Rock, by Carlo Bonone; in the fourth, a sacrifice of Iphigenia, by Alessandro Varotari; and in the fifth, the story of Phaeton driving the chariot of the sun : the designs of all these are beautiful, and hours might be spent in their investigation: in the eighth room is a cartoon of Raphael, representing Noah entering the ark, and two paintings of John the Baptist. The floors are paved with rich mosaic. In La Scuola are some fine paintings of the Annunciation, the Crucifixion, and the slaughter of the Innocents, by Tintoretto; the latter seems a