about 55 double strokes per minute, and the power is applied direct to the crank on the screw axis, without the intervention of gearing, or any kind of multiplying apparatus. The tonnage of the Novelty is 328; and, with 140 tons of ballast on board, her unmerged sectional area is 164 feet. Her power is stated to be only 25 horses, and her speed 8 statute miles.-The Artizan, No. 2; a truly valuable addition to our scientific periodical literature.

The Prince of Wales, built to ply between London and Margate, by Miller and Ravenhill, is a very handsome vessel. Her chief dimensions are-length of keel, 180 feet; breadth of beam, 22 feet; depth of hold, 10 feet 6 inches. Propelled by two engines of 68-horse power.

The Mermaid, with Mr. George Rennie's conoidal propeller, is 130 feet long between perpendiculars, 16 feet 6 inches broad, 9 feet deep in hold, and of 164 tons burthen. She has two engines, on the direct-action principle, of 45 horse power each, which, with the boilers and appendages, weigh altogether only 47 tons. The cylinders are of 37 inches diameter: the length of stroke, 32 inches; number of strokes per minute, 35 to 36. The motion is communicated to the propeller through the medium of two pairs of cog-wheels. The Screw-Propeller, by Mather, Dixon, and Grantham, of Liverpool, has been very successful with an iron vessel, fitted with their patent improvements. The screw is worked direct, without the intervention of spur-wheels, by the aid of a steam engine and boiler on the locomotive principle, consisting of two cylinders 13 in. diameter, and 18 in. stroke, and when light, the screw makes about 85 revolutions per minute; the pressure of the steam in the boiler is about 50 lbs., and is used expansively. The vessel is 65 feet long, 12 ft. 6 in. beam, and draft 3 ft. 9 in.

The British Steam Frigate Penelope has created much interest in the nautical world, by being cut in half and lengthened 63 feet amidships, and transformed from a sailing to a steam frigate. The engines are by Seaward and Capel. There are two of them, conjointly being 700 horse power, although the nominal power is only 620 horse, the velocity of the piston being taken at 220 feet per minute. The diameter of the cylinder is 92 inches, and the length of stroke nearly 7 feet. Every part of the engines and boilers is made adequate in capacity and strength for 700 horse power. The engines are made upon the direct-action principle, and upon the same plan as the engines of the Cyclops, Gorgon, and steam frigates in Her Majesty's steam marine. engines are furnished with an apparatus, by which the paddle-wheels, one or both, can at any time be disconnected from the engines. The chimney of the boiler is arranged like a telescope funnel in two parts to slide into or shut up one within another. She has three masts, and is rigged in every other respect as a sailing vessel, with the exception that the yards connected with the mizen mast will be struck, and only hoisted when required to be used.

The

The Peiki Tijaret (The Precursor of Trade) has been built for the Ottoman Steam Navigation Company, for the conveyance of the mail and passengers between Constantinople and Trebison. She was constructed from the designs of Messrs. Ritherdon and Carr, by Mr. Fletcher, and fitted with engines by Miller, Ravenhill, and Co. Her dimensions aré, length between perpendicular, 168 ft., beam, 26 ft. 6 in., depth of hold, 16 ft. 6 in., and draft, 10 ft. 6 in.; burthen 468 tons, o.M. She has a pair of beam engines of 90 horse power each.

The

The Bentinck Steamer, built for the Peninsular and Oriental Steam Navigation Company, is 250 feet in length from the head to the taffrail, 40 feet in breadth, and 31 feet in depth, and admeasures, including the spar deck, 2,020 tons. Her engines are of 520-horse power, and her cost about £84,000. The Bentinck' was lauuched at Liverpool on the 17th January, 1843. state saloon is about 32 feet square, being the whole width of the vessel at the stern, and is approached by a corridor. On each side are ranges of state cabins, and at the end is the ladies' cabin on one side, and stewards' room on the other. The decorations were designed and furnished by Mr. Bielefield, of London and Liverpool; those in the state saloon consist of a series of ten views from Affghanistan, beautifully enamelled on slate by Steedman; the frames are of Bielefield's papier maché. The ladies' cabin is fitted up with paintings, enamelled on slate, by Heedman, after Watteau. The ship is

divided by iron bulk-heads into five compartments, giving her great safety in case of accident; and there are large cisterns for water, hot and cold baths, improved warming apparatus on the worm-tub principle, and every other essential to make her one of the most complete and efficient steam vessels ever produced.

The Virago is one of the second class frigates belonging to our service. Her dimensions are as follow:-Length between perpendiculars, 180 ft.; keel, 156 ft.; extreme breadth, 36 ft.; breadth for tonnage, 35 ft. 8 in.; moulded breadth, 35 ft.; depth in hold, 21 ft.; tonnage, 994, M.N. She is fitted with two engines of the collective power of 300 horses, manufactured by Boulton, Watt, and Co. which occupy less space than any yet employed in her Majesty's navy or otherwise.

The "Waterman, No. 9," is a little iron steamer, constructed by Napier, of Millwall, for the Waterman's Company, under the guarantee that she should beat every vessel of her class, and burn less fuel; both of which feats she has achieved. Her length, between perpendiculars, is 107 feet; breadth at paddleboxes, 15 feet; depth, 7 ft. 2 in.; draught of water, 2 ft. 9 in. The vessel is propelled by one engine, with a cylinder of 30 inches diameter, and 3 feet stroke, which is supplied with steam by a cylindrical boiler 7 feet in diameter. The boiler is placed in the vessel upon its end, so that it only occupies a superficies of the vessel's floor equal to that of a circle 7 feet in diameter. The bottom of the vessel is made double, and the space between the two bottoms is made available for accomplishing the condensation of the steam by external cold. The boiler is consequently supplied only with clean and fresh water; and should the bottom of the vessel be injured by any casualty, no leakage into the ship can, therefore, ensue. The engine of this "Waterman" is "direct action;" but its directness is of a peculiar description. There are four piston-rods, which are prolonged above the shaft by a distance equal to the length of the connecting-rod. Upon the top of these piston-rods a cross is placed, and from the centre of this cross the connecting rod is hung. The air-pump, feed pump, and bilge-pump, are wrought by a short lever, one end of which is attached by links to the cross. The paddle-wheels are made with leathering-floats, which enter and leave the water perpendicularly, or at any desired angle, in a manner similar to that of Morgan's wheels. The parallelism, however, is differently maintained, being accomplished by a ring suspended in a position eccentric to the wheel by the crank-pins of cranks attached to each float. The most extraordinary part of this vessel, however, is the boiler, which only occupies a circle of 7 feet in diameter upon the bottom of the ship. The fire-grate of the boiler is cylindrical, and is of the diameter of the shell, diminished by the breadth of a water-space all round. Above the fire, a water-space of 14 inches in depth extends all over the grate, with the exception of a space left at that part most remote from the fire-door for the escape of the smoke. All above this horizontal water-space is one large chamber, in the middle of which the chimney is situated; but around the chimney are a number of concentric circles of locomotive tubes, communieating at their under ends with the water in the horizontal water-space, and at their upper ends with the water reposing on the top of the chamber. The hot air proceeding from the fire must, before it can reach the chimney, wend its way through this forest of brass tubes: in which operation it is robbed of its heat to the uttermost farthing. The steam-producing powers of this boiler are very great, and its consumption of fuel moderate.-The Artizan, No. 3.

New Sailing Vessel with Auxiliary Steam Power and Screw Propeller.The Margaret is a new Vessel, to run from Hull to Liverpool, viâ the Caledonia Canal, and constructed of iron, with water-tight bulkheads, on the clipperschooner build, and rigged with proportionate masts and spars, for sailing on all occasions when the wind is favourable. She has two engines on board, of 14 horse power each, working an Archimedean screw (Smith's patent), to be used in calms or when close-hauled. This is the first sailing vessel ever built for carrying a large cargo, with small auxiliary steam power, working a screw. In calm and still weather, this vessel's speed, with only 28 horse power, and a cargo on board of 190 tons dead weight, was upwards of six knots per hour: close-hauled, and reduced to her fore and aft canvas, on applying the screw

her speed was raised from three knots to seven and a half and eight knots, the screw not only destroying the lee-way entirely, but bringing her up to windward of her course; and, with a fresh breeze on her quarter, and all sails set, the screw also at work, she ran nine and a half to ten knots. She beat through the Pentland Frith, in a heavy gale of wind, with the screw entirely disconnected, weathering and beating completely eight or ten merchant-vessels in company, and was only kept way with by a cutter, supposed to be one of the revenne cruisers.-Hull Packet.

ACCIDENTS ON RAILWAYS.

THE official Report, lately published, shows a progressive diminution in the number of Accidents. The last report contained an analysis of the returns of accidents from the 12th of August, 1840, the date of the passing of the Act for the Regulation of Railways, to the 1st of January, 1842, from which it appeared that the number of railway accidents of a public nature, attended with personal injury, during the last five months of 1840, amounted to twenty-eight, by which twenty-two deaths and upwards of one hundred and thirty-one cases of injury were occasioned; while during the twelve months of 1841, the number of accidents of a similar description amounted to twenty-nine, with twentyfour deaths, and seventy-one cases of injury. During the past year (1842), the number of accidents of this description had been only ten, the number of deaths five, of which only one occurred to a passenger while travelling by a train and not observing the proper degree of caution, and the number of cases of injury were only fourteen. These did not include accidents which had happened to individuals owing solely to their own inadvertence and misconduct, nor accidents to servants of the company under circumstances involving no danger to passengers, neither of which could be fairly classed among railway accidents of a public nature. With respect to the comparative safety of railway travelling, a comparison of the number of accidents attended with death or injury to passengers with the number of passengers conveyed by railway during the same period, which appears to have been upwards of 18,000,000, it would seem to indicate that the science of locomotion, as far as the public safety is concerned, has arrived at a very high degree of perfection, seeing that out of more than 18,000,000 conveyed by railway in the course of the year 1842, only one had been killed while riding in the train, and observing the common degree of caution.-Athenæum, No. 804.

HAWTHORN'S NEW LOCOMOTIVE ENGINE.

On the 11th of April, a splendid and powerful New Locomotive Engine, the Star, manufactured by the house of Messrs. R. and W. Hawthorn, Newcastle, made its first trial trip on the railway from Carlisle to the cut in Cardew Mines, a distance of six miles, which, on returning, was passed over in ten minutes, including one stoppage. The trial was in every respect satisfactory, both as regards speed and fuel. The quantity of fuel consumed by this engine is considerably less than any engine upon the common construction. The Star is constructed on Messrs. Hawthorn's patent principle, having return tubes in the boiler, in consequence of which the caloric traverses twice

its length, thus giving it a greatly increased evaporative power.— Carlisle Patriot.

NEW STEAM BREAK.

MR. PETER ROBERTSON, superintendent of the engine department, on the Glasgow and Ayr Railway, has invented, and for some time applied, a very simple and effective Steam Break. The steam being introduced into a little cylinder, at the side of the fire box, presses upon the piston, which is connected almost immediately to a strong iron or steel hoop, which is thus made to apply exactly, and press with great energy upon the circumference of the driving wheel. The effect is to stop the train in much shorter time than can be effected by the ordinary carriage breaksmen.

WOODEN RAILWAYS.

A NEW System of Railroads, composed entirely of wood, has been laid down to test the principle, near Vauxhall Bridge. It is the invention of Mr. William Prosser, who has proved the system. The line laid down, though short, has yet a variety of gradients as well as curves and straight lines, as the following statement will show :-For 33 feet fall, 1 in 25; 85 feet, 1 in 400; 170 feet rise of 1 in 100; 80 feet level, 140 feet fall of 1 in 95; and 25 feet rise of 1 in 12, in which line there is a curve of 720 feet radius. The line is constructed of Scots fir rail, 6 inches square, prepared by Payne's process, that of exhausting the pores of the wood, and injecting, under great pressure, metallic solution, and afterwards lime, which semi-petrifies the wood, rendering it indestructible by damp, &c. It also gives it the properties of resisting pressure and wear to a great extent, while it increases the "bite" of the wheel, enabling locomotives to ascend inclines otherwise impracticable. This being the case, railways can be made at comparatively less cost, as the great outlay is caused by the necessity of having as level a line as possible, and instead of going round or over hills, the practice is now to go through them, to the manifest loss of the shareholders.

There is a locomotive engine at work; this engine, a common road carriage, built by Mr. John Squires, is adapted for running on the wood rail by another contrivance for guiding the locomotive. This consists of an addition of anti-friction wheels fixed to each end of the carriage; these wheels run on bevil axles, and have a double flanch, the inner flanch running parallel to the inside of the rail, and the upper one parallel to the surface, but not touching it, except in cases of accident to the main wheels, when they come on the rail, and convey the carriage to its destination in safety.

THE KINGSTOWN AND DALKEY ATMOSPHERIC RAILWAY.

ATMOSPHERIC propulsion on railways is now an accomplished fact. Several preliminary trials have been made on the line we are about to describe, and very shortly the establishment will be in full operation. The scene of this triumph of science is one line of the train laid down

for the purpose of conveying granite from the quarries of Dalkey for the construction of the magnificent harbour of Kingstown.

It will scarcely be necessary to describe the general principles of the Atmospheric Railway; but there are some details connected with its practical application which it may be requisite to enter into, as the applicability of the system depends principally on the mode of keeping the pipe air-tight. This explanation we quote from No. 10 of the Artizan, a work at once sound and popular, elaborate and economical: In the Atmospheric Railway, a pipe of about 12 inches diameter is laid between the rails on which the carriages run; this pipe is exhausted at one end by an air-pump; a travelling piston is forced along it by the pressure of the atmosphere; and a rod, or plate, of iron, connecting the piston with the carriages, traverses a slit on the top of the pipe. The great difficulty to be overcome was to cover this slit with a substance which would be air-tight, and yet would permit the connecting rod to pass without offering much obstruction.

For this purpose the opening at the top is covered by a continuous valve, extending the whole length of the pipe. It is formed of leather riveted between two iron plates. The upper plate is wider than the slit, and prevents the leather from being pressed in by the pressure of the atmosphere; the lower plate just fits the slit, and is curved to the shape of the pipe. One edge of the leather is fastened to a longitudinal rib, cast along the opening, and forms a hinge, as on a common pump valve. The other edge of the valve, when it covers the opening, forms, with a ridge cast on the pipe, a channel or trough, on its whole extent. This trough is filled with a composition of bees-wax and tallow, which, when melted and cooled, adheres to the side of the valve, and keeps it air-tight. As the travelling piston is forced along the pipe, one side of the valve is raised by four small wheels fixed behind the piston, so as to admit the connecting rod to pass. The opening thus made also admits the air to act against the piston. The rupture thus made in the composition of wax and tallow is cemented again, before the train passes, in the following manner :-A steel wheel, regulated by a spring, is attached to the carriage, and presses down the valve immediately after the connecting arm has forced it open, and a copper heater, about 5 feet long, filled with burning charcoal, passes over the composition and melts it, thus leaving the valve air-tight as before, and ready for the next train. A protecting cover, formed of thin plates of iron about 5 feet long, and hinged with leather, is placed over the valve, to protect it from the rain or dust. It is contemplated to have each pipe about three miles long, with a stationary engine for each length of piping to exhaust the air; and an arrangement is made, by means of which the piston, as it approaches the end of the pipe, opens a valve which admits it into the next length of piping, so that the train may proceed without stopping.

It is evident that as the tractive force is derived entirely from the pressure of the atmosphere on the piston, its amount will depend on the area of the piston, and on the extent to which the exhaustion of