Inferieure, and a fifth at Lyon. We believe there are none ramaining in England.

We have experimented with the three of the department of the Seine. The oldest is at the abattoir de Grenelle, and was constructed by Manoury. The two others are in the Vigier baths; they were made by Gingembre.

The following numbers were obtained from these three machines in three series of experiments :

Experiment of the 26th of March, 1833, on

the bath machine of Pont Marie. Temperature of the water of the Seine, 64° Mean tension of the steam, 3atm. Water raised per hour, 12.213m. Height of elevation, 6.6m. Temperature of the water raised, 104° Dry wood burned during one hour, 30.4k. Duration of a period, 26.0"

Experiment of the 10th of July, 1833, with the same machine.

Temperature of the water of the Seine, 194°
Mean tension of the vapour, 3atm.
Water raised per hour, 12.724m.
Height of elevation, 6.10m.
Temperature of the water raised, 23°
Dry wood burned in an hour, 46kil.
Duration of a period, 26"

Experiment with the machine of Manoury
D' Hectol.

Temperature of the water of the well, 121°
Mean tension of the steam, 00
Water raised per hour, 15.400m.
Height of elevation, 14m.

Temperature of water raised, 161°
Charcoal burned in an hour, 13kil.
Duration of a period, 90"

Agreeably to the first and second tables, the machine of Pont Marie gives 2.595 dynam, to a kilogramme of wood.

This is about eight times less than the effective force of a small piston machine of the same force which would work pumps. But the water raised would have to be afterwards heated, so that we must take into account the increase of temperature, which was four degrees Cent. (=7 F.) in the first series, in the month of March, and three quarters in the second in July. Thus, in the first case, each kilogramme of wood sent up to the reservoir, by the action of the machine 1702, portions of heat (caloric) and the second 1255. With a more complicated machine than that of Savery, an additional heating apparatus would have been necessary, and this addition would have required the same expense.

Thus, whenever water is to be both raised and heated (and this often occurs in manufactories) the almost forgotten machine of Savery is the most advantageous motive

power.

285

It is the least costly at first, the least subject to accidents, and to wear and tear, and the most easily managed.

We will add a few words on the comparative effect of the three machines. In all of them the accession of heat was about four degrees, although the Manoury machine differs essentially from the two others.

The last machine performs more than double the work of those of Gingembre, at the same cost. Agreeably to the public report of M. Girard, in the 21st Vol. of Annales de Physique et de Chimie, the Manoury machine gave 20,202 dynam for each kilogramme of charcoal. This result surpasses that obtained by us, whence the increase of temperature of the water must at that time have been at a maximum of 2.8° instead of 4°. This measure is wanting in the memoir referred to.

From the foregoing experiments it results: 1. That the Savery Machine is a very valuable motive power which may be advantageously employed in many of the arts.

2. That the use of it ought to be limited to those cases in which water is to be heated as well as elevated.

3. That the machine of Manoury is the best model for imitation.-Ann. des Pontes et Chaussees, trans. in Frank. Journal.

ON FOUNDATIONS UPON SAND, AND ON COATINGS OF MINERAL TAR BY M. OLIVIER, ENGINEER.

The

1. Foundations on sand.-At the school des Pontes et Chaussées, in 1830, it had been pointed out, that foundations on sand might be laid, wherever the earth was compressible, and in no danger of being carried away by floods. The canal of Saint Martin was given as an example. I have several times applied the system thus indicated and always with success. following are examples: M. Dupuis, one of the conductors in my district, an architect of the town of Pont-Auderner, was employed to erect a building for the mayoralty. Its situation required that the edifice should be founded on the natural soil. This was well, for there is, in the valley of the Rille, a little below the soil, a bed of solid stones, mixed with sand, of about 31 inches thick. M. Dupuis, feared that the ground under the bed of gravel was not good, and he had it sounded. It proved to be compressible, and when the gravel was removed, it became impossible to lay a good foundation on the earth which it covered. The architect deemed it needful, in consequence, to resort to piles, and these, it was ascertained, must be very long

to reach solid ground. I went to see the work as they were beginning to drive the piles it was a very expensive undertaking, which I proposed they should avoid, by substituting a bed of water sand, well watered with cream of lime. M. Dupuis, being responsible for the work, could not decide upon taking this advice, and continued the piles sufficiently for the whole front wall; but he adopted for the other walls the plan I had recommended. These were all, of course, united, though resting on different foundations, but they have all remained firm without any movement, or at least it has been uniform.

This furnishes a new proof of the safety of foundations on sand; 1st, since all the erections in the valley of the Rille, founded on the bed of gravel before mentioned, stand very well, though the ground underneath is compressible; 2nd, since the walls placed on sand, resting on soft ground, have not sunk more than those built on piles, driven with the greatest care to a solid foundation.

Another fact. M. Fauquet Lemaitre, is a proprietor at Bolbec of several cotton factories. One of them being burnt down, he extended the other, which made it necessary to connect the new with the old walls: these walls, situated at the foot of a hill, were partly on a mass of chalk and partly on a bottom of green sand, in spaces where no chalk existed. This sand was moistened by infiltrations of water, which could not however wash it away. When a weight was placed on this sand and left at rest, the mass remained firm; but if a little motion were given it, it became pasty and almost liquid. The builder thought he must have recourse to piles, and several foundations were prepared for their being driven, when M. Fauquet spoke to me about his buildings, and of the position in which he found himself. At this time, the experiment before cited had been made, and I advised him to lay his foundations on sand. I requested him to converse with M. Frissard, chief engineer at the Port of Havre, and he did so.

The latter coincided with me, and added that all the masonry of the steamengine of 60-horse power, was founded on sand, and nothing had moved it. It was not so with the structures on piles; a side wall, connected with the foundation of the engine, placed on piles driven as deep as possible, had moved so much that the connecting stones were broken, so that they had to saw them off from the engine walls, the level of which had not changed. This accident, it was believed, occurred from the water contained in the sand, having collected more abundantly around the piles; and the friction of the latter against the

ground, being thus diminished, they sunk until the masonry rested on the sand.

As other walls erected on sand or on rocks, have not moved, this experiment proves that foundations on sand are as safe as those on rocks, while we cannot rely upon the stability of an edifice constructed on piles and driven into sand; the friction which they encounter induces the belief that they have gone as far as possible, or necessary, and when any cause diminishing this resistance from friction occurs, an accident follows which proves the contrary.

The first experiment was made under my own eyes; the second I did not witness, but have every reason to believe that a true account was given me.

2. Employment of mineral tar in structures of masonry.-It has for a long time appeared to me that mineral tar, which does so well upon wood and iron, might also be used for covering stone and brick work, as a defence against moisture. Four experiments were made which confirmed this apprehension. But it will be well to premise that as mineral tar is obtained by distilling vegetable materials, it would be more suitable to call it pyroligneous tar.

Without touching upon all the cases in which pyroligneous tar may be employed, which we believe to be very numerous, we shall simply cite a few in which we have tried it.

The light house of Quillebuef had become much degraded by North East storms. The rains were very copious, and the water passing into the brick tower, caused the bottom of the staircase to rot. We repaired the masonry, and in the month of May, 1833, painted the tower with pyroligneous tar, which so far has perfectly answered our expectations; excepting that a few of the pilots pretend that the light-house, being now black, is not seen so well as when it was white,

M. de Cachelu painted with the tar an earthen wall, exposed to the rains so much as to become very wet inside the building. When I saw these walls, the tar had served as a complete defence against the dampness.

Walls much exposed to storms of rain, are commonly defended by a coating of slate or cement, but the above experiments show that these two modes of defence may be advantageously replaced by a coating of pyroligneous tar.

The joints of the wall being well filled up and smooth, the tar is spread over it and it penetrates the wall. When dry, a second coat is applied and immediately powdered over with sand. This, when solidified, is covered with lime white-wash, as thick as can be put on with a brush. This acting

LIST OF ENGLISH PATENTS GRANTED BETWEEN THE 24th OF DECEMBER, 1838, AND THE 24th OF JANUARY, 1839. Samuel Clegg, of Sidmouth-street, Gray's Innroad, engineer, for a new improvement in valves and the combination of them with machinery. Jan. 3; six months to specify.

Henry Robert Abraham, of Keppel-street, Russell-square, architect, for improvements in apparatus applicable to steam-boilers. Jan. 3; six months.

Thomas Nicholas Raper, of Greek-street, Soho, gentleman, for improvements in rendering fabrics and leather waterproof. Jan. 3; six months.

Abel Morrall, of Studley, needle maker, for certain improvements in the making or manufacturing of needles, and in the machinery or apparatus employed therein. Jan. 3; six months.

Louis Mathurin Busson du Maurier, of Lombardstreet, gentleman, for improvements in the construction of springs for carriages. Jan. 3; six months.

Miles Berry, of Chancery-lane, for certain improvements in rotatory engines to be worked by steam or other fluids. Jan. 4; six months.

William Hickling Burnett, of Wharton-street, Bagnigge Wells-road, gentleman, for new and improved machinery for sawing, planing, grooving and otherwise preparing or working wood for certain purposes. Jan. 8; six months.

Joseph Clisild Daniell, of Limpley Stoke, Wilts, for an improved method of weaving woollen cloths and cloths made of wool together with other materials. Jan. 9; six months.

Moses Poole, of Lincoln's Inn, gentleman, for certain improvements in clogs. Jan. 11; six months.

John Howarth, of Aldermanbury, manufacturer, for certain improvements in machinery for spinning, roving, doubling, and twisting cotton, and other fibrous materials. Jan. 11; six months.

John Ashton, of Manchester, silk manufacturer, for an improvement or improvements in manufacturing plush of silk or other fibrous materials. Jan. 11; six months.

John Swain Worth, of Manchester, merchant, for an improved machine for preparing and cleaning wool for manufacturing purposes. Jan. 11; six months.

William Newton, of Chancery-lane, for certain improvements in machines for drilling land or sowing grain and seeds of different descriptions. Jan. 11; six months.

Francis Brewin, of the Old Kent-road, tanner, for certain improvements in using materials employed in tanning, and preparing the same for other useful purposes. Jan. 11; six months.

Robert Logan, of Trafalgar-square, for a new cloth or cloths constructed from cocoa nut fibre, and for certain improvements in preparing such fibrous materials for the same and other purposes. Jan. 11; six months.

William Ponsford, of Wangye-house, Essex, gentleman, for an improvement in the manufacture

287

of hats, and an improved description of felt suitable for hats and various other useful purposes, and improvements in preparing the material or materials chiefly used in the manufacture of such felt. Jan. 12; six months.

Edwin Marten, of the village of Brasted, Kent, plumber, for an improved method of laying covering composed of lead or other metal on the roof of houses or other buildings, with drains, whereby the part of the water falling on such roof which would otherwise penetrate, is carried off, and rolls and seams are rendered unnecessary. Jan. 12; six months.

Joseph Burch, of Bankside, Blackfriars, calico printer, for certain improvements in printing cotton, woollen, paper and other fabrics and materials. Jan. 15; six months.

William Witham, of Huddersfield, machinest, for improvements in engines to be worked by steam-water or other fluids. Jan. 15; six months.

Hugh Ford Bacon, of Fen Drayton, Cambridge, for an improvement or improvements in apparatus for regulating the flow or supply of gas through pipes to gas burners, with a view to uniformity of supply. Jan. 17; six months.

William Holme Heginbotham, of Stockport, gentleman, for certain improvements in machinery or apparatus for propelling boats or other vessels, to be employed either for marine or inland navigation, and to be worked by steam or other power. Jan. 17; six months.

William Newton, of Chancery-lane, civil engineer, for certain improvements in engines, to be worked by air or other gases. Jan. 17; six months.

Oglethorpe Wakelin Barratt, of Birmingham, metal gilder, for certain improvements in the process of decomposing muriate of soda, for the manu facture of mineral alkali and other valuable products. Jan. 19; six months.

Joseph Garnett, of Haslingden, dyer, for certain improvements in machinery or apparatus for carding cotton, flax, wool, or any other fibrous substances. Jan. 19; six months.

Richard Dugdale, of Paris, now residing at Manchester-street, Middlesex, engineer, for a method or methods of increasing the security, tenacity and strength of beams, axles, rods and other articles made of iron and steel. Jan. 19; six months.

Caleb Bedells, of Leicester, manufacturer, for an improvement in gloves, stockings and other articles of hosiery. Jan. 21; two months.

John Coope Haddan, of Baring-place, Waterloo Road, Surrey, civil engineer, for improvements in machinery or apparatus for propelling vessels and boats by steam or other power. Jan. 22; six months.

George Stevens, of Stowmarket, brewer, for certain improvements in stoves. Jan. 22; six months.

Thomas Dowling, of Chapel-place, Oxford-street, gentleman, for improvements in preparing metals for the prevention of oxidation. Jan. 24; six

months.

consumption of such and other kinds of fuel. Dec. 17.

John Milling, for improvements in locomotive steam-engines to be used upon railways and other roads, part or parts of which improvements are applicable to stationary steam-engines or to machinery in general. Dec. 21.

John M'Dowall, for improvements in the machinery for sawing or cutting timber, and in the mode of applying power to the same. Dec. 22.

Daniel Stafford, for improvements in carriages. Dec. 26.

NOTES AND NOTICES.

Artificial Suns.-In our 797th number, p. 112, we noticed the proposition of M. Gaudin to give artificial light to the city of Paris from an elevated Drummond light. Our attention has been called by our valued correspondent Mr. W. H. Weekes, of Sandwich, to a similar proposition of his, published in our 15th vol. p. 255, June, 1831, more than seven years ago. Mr. Weekes also states, that "during the greater part of the last year he has been endeavouring to make arrangements for the purpose of carrying an experiment of the kind into effect from the top of one of the church towers in Sandwich, in lieu of a more convenient and elevated situation."

National Swimming Society.-At a meeting of this Society on the 15th inst. a silver medal bearing the emblems of the society, was presented to Mr. John Fennymore, as champion in swimming for the year 1838; aud another silver medal was awarded to Mr. Mason, of Furnival's Inn, for the best essay on the subject of swimming.

The

Pistrucci's Mode of Medal Striking. following 99 protest against Signor Pistrucci's claim to the new mode of medal striking has been published by M. Caque, Engraver in the Gallery of the Kings of France, at the Paris Mint, in a French Journal. "M. Pistrucci, who holds a station in the Mint at London, is announced as the inventor of a process for striking a matrix with a punch which has never been touched by the graver, and which gives, nevertheless, a medal identically the same as the original model in wax.

In this opera

tion, the beauty and perfection of the design are, at a single blow, transferred to the metal, whether of gold, silver, or copper. The process is this: The model being given in wax, earth, wood, or any other convenient material, take a mould of it in plaster, when the mould is dry or oiled: to harden it, take an impression of it in the moulding sand for cast iron, as fine as possible, in order that the points may be sharp, and that the materials may become as hard as tempered steel. The back is to be dressed to a plain surface. This piece, solidly fixed in a piece of steel, becomes the matrix, on which may be struck either the medal itself or a punch, if it be desired to multiply steel matrices of the medal. M. Pistrucci has tried his process on medals three inches in diameter, and with perfect success. The importance of such a discovery is very obvious. Not only medals, but many pieces of jewellery which require to be chased, may be treated in the same manner." Permit me to say, Mr. Editor, that this important discovery, as you may be easily convinced, is two years and a half old. At that epoch I made known at the Royal Mint in Paris, all that M. Pistrucci has just done in London. A plan of the apparatus, and the details of the operation were deposited by me in the Royal Mint, to be placed at the disposal of my fellow labourers in France. They are in the cabinet of the Director of the Mint. Since that time the

medal engravers have employed my process, and more than thirty medals of the reign of Napoleon, have been thus reproduced. You may easily, Mr. Editor, obtain a proof of my statement on application at the Mint."

Varnish for common Candles intended as a substitute for Wax Candles.-Take equal parts of the balm of benzoin and resin mastic; put each of them in a separate vessel of glass or lead, add spirits of wine, and heat them gently till the resinous parts are dissolved. Let each of the solutions remain a while at rest, and then unite them in one vessel. Prior to using this composition, it is adviseable that the fluid be heated to 25 deg. or 30 deg. cent. ( 80 or 90 Fah.) Dip the candle in it from 5 to 10 seconds, then dry it carefully, which will take about 10 minutes. The proportion of the ingredients may vary, but in proportion as the benzoin is diminished and the mastic increased, the candles become more liable to soften by handling. If the benzoin be increased, the candle dries too soon and loses its polish and colour. The quantity of alcohol will vary according to the thickness of the coat to be given to the candle.

To dye Wool and Goat's Hair a delicate Blue.M. Buisson, apothecary, has communicated to the Royal Society of Agriculture at Lyons, a new and very simple process. The colour is strong enough to resist water, the sun, and even soap; while that obtained by dye-woods fades much more easily, and is very inferior in brightness in an artificial light. To obtain this colour as pure, fresh, and deep as possible, the water of the bath while cold, must be first saturated with crystallized verdigrease (acetate of copper), then slightly acidulated with acetic or pyroligneous acid; dip the stuffs in the usual way, then wash and dry them.

Electric Power of the Gymnotus.-At the first evening meeting of the Royal Institution for the session, held on Friday evening, Dr. Farraday delivered a lecture on the Electric Powers of the Gymnotus and the Silirus. He stated that an interesting specimen of the former was now in this country, which has enabled him to make some experiments upon its electric powers. The first part of his lecture was devoted to an explanation of the phenomena of electrical action, and he then explained the apparatus by which similar effects were produced by the fish to those of an electrical machine when in action. They consisted in copper collars, lined with indiarubber, placed near each extremity of the fish, with which conductors were connected, and amongst other phenomena the formation of a helix was very obvious. He also announced that another fish was daily expected in this country, which could afford further opportunity for experiments. One surprising part in the economy both of the electric ray and eel was, that the organs of life constituted but a small part of the animal, the rest being mere electrical appendages, and which it had been proved might not only be removed without injuring them, but that the fish even attained greater vivacity and lived longer. Now this afforded a room for believing, that further experiments would throw greater light upon the nature of the nervous influence, and he suggested as an experiment the removal of these appendages and the trying the effect of passing electrical currents into them. The lecture was illustrated by some of the most splendid apparatus in the possession of the Institution, and the demonstrations were given in the lecturer's most happy manner.

Errata in Col. Maceroni's article On the Requisites of a good Gun. No. 802, p. 198, col. 2, line 7 from bottom, for "circle" read" cube. "-p. 200, col. 2, line 4, for "town" read "Tower."