for which the only additional charge would be the cost of oil and coal, as. the wear and tear of apparatus, rent, &c. would be the same as at pre sent. Two pair of retorts are suffi cient to supply the requisite quantity of gas, amounting to about 6000 feet per night, the expense of preparing which is about 36s.; but were more required, it would be much less.

The quantity of gas procured from different oils varies considerably. Whale oil is considered the best, and next to it is cod oil, from eight tons of which 201,500 cubic feet were obtained. There are other oils of inferior price, but these ought not to be used, because they not only give less gas, but are injurious to the works. In conveying coal gas through the pipes, there is a considerable waste, either from it sacting on them, or escaping; but this does not happen with oil gas. To the consumer the advantages are equally great; an individual, near the works, has in his shop five large burners, burning from sunset till nine, and on Satur days till eleven. He has other three, but as these do not burn so long, they are estimated at one and a half, making in all six and a half. The average number of hours of burning per week is twenty, or 1040 in the year. The consumption of gas, 8800 cubic feet, for which he is charged 217. The light of the burners consuming one and a quarter foot per hour, is fully equal to, if not exceed ing, that of coal gas, consuming at the rate of five feet. The benefits arising from its introduction into private houses are equally great. There is not a single annoyance, nor the slightest inconvenience, from its use, while the brilliancy of the light is superior to that of coal gas. Supposing the same expense incurred as for common tallow candles, double or even treble the light is afforded; four or five times as much, if compared with sperm oil; and above twelve times as much, if the comparison be made with wax candles. ORNAMENTING STEEL AND OTHER METALS WITH THE PRISMATIC COLOURS.

The production of the prismatic tints by scratches on the surface of metallic and transparent bodies was first observed by Boyle, but after

wards more particularly examined by Dr. Young, who ranked them in the class of optical phenomena, known by the name of the "colours of striated surfaces."

Mr. Barton, of the Mint, has lately conceived the idea of ornamenting steel and other articles in this way, and has secured, by patent, the exclusive privilege of applying this principle to practical purposes. The excellence of Mr. Barton's instrument, which was constructed by the late Mr. Harrison, depends chiefly on the beauty and correctness of the screw. The plate of this is not divided higher than the 2000th part of an inch; but Mr. Barton has drawn divisions on steel and glass so minute as the 10,000th part of an inch. In drawing lines of the former dimension, he often leaves out one line intentionally; and the greatest proof of the stability of the engine is, that having taken off the brass table with the work on it (when the omission is distinctly perceived), he can restore it to its place, and introduce the line without its being distinguished from the rest. In applying the principle of striated colours to ornament steel, the pattern is produced on the po lished surface by the point of a diamond, so that either the whole or a part of the surface is covered with grooves, the distance of which from each other may vary from the 1000th to the 10,000th of an inch. When these lines are most distant, the pris matic images of a candle, seen by reflexion from the polished surface, are nearest one another, and the com mon colourless image; and when the lines are least distant, the coloured images are farthest from one another, and the colours are most vivid. In day-light, the colours produced by these minute grooves are scarcely distinguishable, unless at the boundary between a dark and a luminous object. In sharp lights, however, particularly in that of the sun, they shine with extraordinary brilliancy; and the play of tints, which accompany every luminous image, can be equalled only by their matchless exhibition in the reflexions of the diamond. The surface of fine steel, therefore, when grooved by the delicate instrument of Mr. Barton, is peculiarly fitted for imitative jewels, and other articles of female dress;

and there is no doubt that it will prove useful for many other purposes. The divisions he commonly employs for his metal ornaments are 2000 to an inch, but when the material is good, his engine enables him to divide to 5000, or even to 10,000; when, however, the lines are SO close, the labour is very great, but the beauty of the work is generally sufficient to compensate the time bestowed on it, as the beauty increases with the number of lines. The depth of the groove has a great effect in producing brilliancy, owing to the increase in the quantity of reflected light.

LUMINOUS PROPERTY OF THE OCEAN

AS DERIVED FROM INSECTS.

In the Memoirs of the Academy of Sciences, there are some interesting observations on two minute marine animals, one of which is very remarkable for its phosphorescent qualities. During a voyage made by the author to the East Indies, he observ ed, that in north latitude 8° 47', and east longitude 73° from Paris, the sea appeared like a sheet of fire, each portion of its surface, when gently agitated, breaking into a thousand stars. The more distant swelling of the waters, presented the appearance of a moving plain covered with snow, and the wake of the vessel was of a clear and luminous white, sprinkled over with brilliant spots of azure light. He was struck by the light, shed by certain small bodies, which frequently remained attached to the helm, when the sea for a moment retired, and ordered a bucket of water to be drawn up and filtered through a fine linen handkerchief. After this it was not luminous, but the handkerchief was covered with many brilliant spots, some of which he raised on the end of his finger, and found that they had the consistence of animal bodies; being thus exposed, they gradually lost their brightness, and resembled the eggs or spawn of fishes. Being anxious to examine one in a clear light, he placed it under a strong magnifying glass, when he observed a sensible movement in its interior, and having put a drop of water on it, it immediately became surrounded by a brilliant fluid. Having filtered another portion of water, and placed the handkerchief in pure sea water, he observed a number of APRIL, 1823.

small insects swimming about with celerity, which, at first sight, resembled those called in France water fleas, one of which he succeeded in catching on a hair pencil. Owing to the slight pressure to which it was subjected, it emitted a luminous and bluish coloured fluid, the traces of which extended in the water to the distance of two or three lines, and when placed under a microscope, it was observed to be surrounded by the cerulean liquid. Many of the most lively specimens of these animals having been put into fresh water, very clear, and freed from all impurities, were immediately precipitated to the bottom, became strongly convulsed, and died in about six seconds; and some, when expiring, gave out a quantity of their bright phosphoric light. For producing this phosphorescence, it seemed necessary that the insect should be in a state of humidity. When the moisture was absorbed, none shone even when bruised. When placed in the water, from which they had been taken, they very soon died, but that in which they had been preserved shone with a very lively light; the phosphoric matter, however, when collected, lost its luminous property in about three days. This little insect appeared to be enclosed in a scaly covering, its general contour resembled that of an almond split down one side, and a little sloped at its superior extremity. The posterior part of its body presented many globules in the form of a moveable cluster, of a bluish colour, and from which the phosphoric matter is provided. Its superior part is furnished with four moveable antennæ or horns, formed of many articulations, and terminated by tufts of very fine hair. The head is placed on the centre, and armed with small hooks. Beneath it are two feet bent, and furnished with hooks, and lower down there are other organs of movement.

PRESERVING FISH BY SUGAR..

Sugar, according to Dr. Macculloch, is a very powerful antiseptic, and though sparingly employed in the curing of hams, it is one of the most active substances in their preservation. Fish may be preserved in a dry state, and perfectly fresh, by means of sugar alone, and even by a very small quantity. He has thus

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tification. The two parts of the tenth volume of Medicine contain the letters M and N. The most remarkable articles are Mourant, Mouvement Musculaire, Musique, Mutisme, Nourriture, &c. Each of these articles is a treatise of itself.

The first and second volumes of the Classical Dictionary of Natural History are now published. The direction of this new work is confided to M. Bory de St. Vincent. Many of the most distinguished naturalists are engaged in it, and great expectations are entertained of it: the volumes now published give reason to hope that they will be realised. The first two volumes of a new edition of the works of Brantôme are just published; it is printed from the edition of 1740, which was collated with the MSS. in the Royal Library. Several considerable pieces, hitherto unpublished, will be added to this edition, which is to be in eight volumes. It is printed to match the great Collection of Memoirs relative to the History of France, from the reign of Philip Augustus to the peace of Paris, in 1763, of which fortyeight volumes are published; it will amount to nearly one hundred volumes. A livraison of four volumes has just appeared, being vol. xxvii. and xxviii. of the first series, containing the end of the Memoirs of Vieilleville, and the beginning of the Memoirs of Boyvin Duvillars; the two others, are the 19th and 20th of the second series, containing the end of the Memoirs of Rohan, and the first two parts of those of Bassompière.

The valuable publication of the Chef d'Euvres des Théâtres Etrangers has arrived at the 16th volume, which is taken up with the Swedish theatre. It contains two comedies, and two tragedies-Odin and Virginia. To this volume is prefixed an excellent essay, under the title of Coup d'Eil sur la Littérature Suédoise.

The third volume of the Galerie Morale et Politique of Count de Segur, contains some pleasing, and some remarkable articles; among the first, are, On Benevolence, On Truth, On Caricatures: among the latter, Le Palais Royal, ou Histoire de M. Duperno, a tale; the Portrait of a Modern Sage; and of Prince Potemkin,

the favourite, general, and minister, of Catherine II. In the last, it will be remarked, that M. Segur, who was ambassador at that time at the court of the Semiramis of the North, has naturally made his narrative very interesting, since he relates what he saw and heard.

Volumes xxxiii. and xxxiv. of the Universal Biography are published; they contain part of the letter P.

The success of the Collection of Memoirs, relative to the French Revolution, has induced the publication of a Collection of Memoirs relative to the English Revolution; two volumes are published, containing the Memoirs of Warwick, in the reign of Charles I., and the first volume of Thomas May's History of the Long Parliament. The following livraisons will contain the Memoirs of Fairfax, Ludlow, Price, Thomas Herbert, Sir William Temple, Major Huntingdon, Bishop Burnet, Lord Clarendon, &c.

Bosnia, considered in its Connexions with the Ottoman Empire, by M. Charles Perthusier, though forming a complete work of itself, is only the third part of a more considerable work, the three volumes of which are to contain the "Political and Moral View of the Ottoman Empire." After having given a rapid sketch of the history of this important province, and mentioned the various people who inhabit it, M. Perthusier describes the geography, natural history, and statistics of Bosnia; he paints the manners, character, and customs of the inhabitants; examines especially the state of commerce and manufactures throughout the Ottoman empire; reviews the government, the administration of the system of finances, the mode of levying the taxes, and their nature; and, finally, he considers Bosnia in a military point of view.

The Flore Medicale des Antilles, by M. Descourtilz, is a work which has been highly commended by the Royal Academy of Sciences, and more particularly by Messrs. Cuvier, Desfontaine, and Dumeril. This work, the result of six years' residence in the Antilles, is every way worthy of recommendation; the matter is new and interesting, the coloured engravings are well execut

ed, and the price is very moderate; in this particular it has the advantage of the splendid work of M. Tussac, which is not yet finished.

A new novel, called Han d'Islande, has been published, of which a French journal says, "It must be hoped, for the honour of French taste, that this work is only an imitation of some foreign production. It is a compound of Melmoth, Bertram, and the Vampyre, together. I know not what evil génius hovers over our literature; but its influence, which would not be dangerous if it acted only on minds of a lower order, seems sometimes to extend even to writers of real merit, who, wantonly forgetting their proper mission, deviate from the rules laid down by taste, to contend in extravagance and bizarrerie, with authors without talents, who take exaggeration for sublimity, horror for interest, and noise for glory."

Before the disasters which have lately ravaged Greece, many rich and enlightened merchants had employed large sums for the purpose of printing, in modern Greek, many useful works, which might tend to raise their countrymen from the state of profound ignorance into which they had been plunged by four centuries of slavery. Soon their views extended, and the immortal works of the ancient Greeks were reprinted, at the expense of their descendants, in their original tongue. The inhabitants of Chios contributed largely to this noble object; and it was at their expense that the two finest treatises of Aristotle, "On Morals," and "On Politics," were published by Dr. Coray. M. Thurot, Professor in the Royal College of France, has made a French translation, from Dr. Coray's edition, the profits of which are to be employed for the benefit of the Chiots who have survived the ruin of their beautiful and flourishing island.

Germany. The numerous emigrations from Germany to the United States of North America, and the deplorable fate of thousands of unfortunate persons, who have been induced to risk their fortunes in the new world, have induced several friends of humanity to procure the most authentic accounts of the actual

state of North America, and of the prospects that await emigrants in that country. Thus Baron Von Gagern sent his nephew to travel there, and collect, information, which he published, to inform his countrymen under what circumstances emigrants might hope to succeed, what precautions should be adopted, and what classes of persons would be likely or unlikely to better their situation by emigration. This little pamphlet did infinite service. Since then other travellers have laboured to the same effect. The latest of these is M. Frederick Schmidt, who has published two volumes, which are to be succeeded by one or two more, in which he gives a very minute account of every thing relative to that country. His opinion is that the United States are not so flourishing as they have been. He gives no very flattering picture of the manners, or the government; above all, he paints in frightful colours the dreadful swindling system which is carried on by the immense number of banks without capital, which are so thickly spread over the United States. To state their exact number is impossible, some failing, and new ones rising daily; but it may be estimated that there is one bank for every 10,000 inhabitants. "The whole paper system," he says, "as it has hitherto been carried on in the United States, is only a school of the most refined arts, to plunder the rich of their property, to encourage a gambling spirit, and to clothe the cunning beggar in silk and purple. It is a paper aristocracy, which is in the highest degree oppressive and disgraceful, and undermines the morality as well as the liberty of the people. The facility with which rags might be converted into gold, has banished the laudable habits of regular industry, and encouraged idleness and dissipation. Hence the innumerable bankruptcies which have latterly occurred in this country; hence the decline of prosperity, and the ruin of the happiness of the citizens."

Dr. F. W. Von Schubert has in the press Travels through Sweden, Norway, Lapland, Finnland, and Ingermania, in the years 1817, 1818, and 1820. 3 vols. 8vo. The first volume will be published at Easter.