panded into upwards of seventeen hundred times its volume, and exerts a mechanical power equal to raise a ton 1 foot high. But it is a law of steam that its density is always equal to the pressure that it is raised under: remove then half the pressure, and the steam will expand into double the space, exerting a mechanical power equal to support half the original pressure. Place two tons upon the piston, and the steam will then only occupy the space of 6 inches; that being in strict accordance with the above named law.

(To be concluded in our next.)

RECENT AMERICAN PATENTS. [Selected and abridged from Mr. Keller's Reports in the Franklin Journal.].

AN IMPROVEMENT IN DOOR-LATCHES. James M. Hoggan.-This is for an improvement on that kind of mortise latch in which the bolt is thrown back by turning the knobs either to the right or left, the projections or levers on the spindle being located within an opening in the body of the bolt, and acting on the back face thereof. The alleged ohjection to the old plan, which it is the object of the present modification to remove, is the small extent of motion given to the bolt, or if not this, the great width required to be given to the opening, in the bolt to receive levers or projections on the spindle of sufficient length to give the required motion to the bolt. To remedy this defect, four cogs are made on the spindle above, two above and two below, and one above and one below in the space or opening in the bolt. The first cog above and below on the spindle are on the same plane, and act against the back face of the opening in the bolt, and the other two are on a plane further back and act on the cogs of the bolt. This arrangement of the cogs is necessary to admit of pushing back the bolt by turning the knobs in either direction; for when the upper cogs are in action, the lower cogs pass by each other, and vice versa, which would not be the case if all the cogs were on the same plane. Another improvement is for adopting the spindle to doors of various thicknesses, by tapping the spindle for the reception of the knobs, which screw on, and providing a slot at each end, instead of a hole, for the securing pin.

IMPROVEMENTS IN THE COTTON PRESS. JEDEDIAH PRESCOTT. The follower of this press is operated by means of two parallel levers jointed to the underside of it (one at each end) and to a carriage, that runs on truck rollers on the bed of the machine, and is worked by cords passing round pulleys and extending to a capstan. The ends

285

of the box are let into grooves in the follower or platen of the press, and work up and down with it, and at the end of the operation they are lifted out of these grooves and liberated by two short levers that strike against projections on the frame-these levers are designated in the claim by the letter z. The lower edges of the sides of the box are jointed to the frame, and, when closed, are held in place by two bars, which are thrown up towards the end of the operation, by pins connected and moving with the platen.

Claim.-"What I claim as my invention, is-1st. The combination of the inclined parallel levers with the horizontal carriage and rollers, arranged and operated in the manner and for the purpose set forth. 2nd. The arrangement of the ends d of the box grooves in the platen, so as to rise and fall with the platen, and be liberated from it at the termination of the pressing. 3rd. The combination of the levers z with the platen, arranged and operated in the manner and for the purpose above set forth. 4th. The manner of disengaging the bars from the box, by means of the pins upon the ascending ends of the box, in order to throw open the sides of the box, to tie and remove the bale."

IMPROVEMENTS IN THE TIDE MILL. JOHN GERARD Ross.-The wheel is placed in a race, at one end of which there is a tide gate hinged to a wall beyond the end of the race and shutting against either side of the race; and at the other end of the race there are two current gates, one termed the "inner current gate," and the other the "outer current gate;" these are hinged to the ends of the race-way wall and shut against a pier placed beyond the end, and in a line with the middle of the width of the race-way. The current in passing along opens the "current gate," and after acting on the wheel passes out through the "outer current gate," and on the return, tide the pressure of water closes this "outer current gate," which causes the current to pass round to that side of the tide gate opposite to that at which it entered on the rise of the tide, throws it against the opposite side of the race-way, acts on the same side of the wheel as on the rise of the tide and passes out through the "inner current gate." The dam walls are formed with pits open at the sides for the free ingress and egress of the water to act on floating caissons which sustain the wheel and always keep it at the required elevation. The shaft of the wheel (or wheels) is connected with the frame work of the mill by bars radiating from the axis of a cog-wheel, into which mash the cogs of the master wheel.

Claim.-"First. I claim as new, and of

my invention, the mode described of fitting the tide-gate, at one end of a race-way, formed by an inner and outer dam-wall, in combination with an outer current-gate, and an inner current-gate, at the opposite end of the race-way; the whole constructed and operating substantially as herein described.

Second. I claim the mode of forming the dam-walls with pits, open at the bottom, to receive and float the caissons that carry the

water-wheel; and the combination therewith of the described means for regulating, adjusting, and directing the ascent and descent of the wheel or wheels, substantially as the same are described and shown herein.

Third. I claim the combination of the described mode of fitting the gates and wheel, and making them act together in the manner described herein."

Boethomonochier, or machine for assisting one-handed persons to feed themselves.

....

Philosophical corn and bunion shield.

67

Thomas Gibbons

552

9

553

square

Fitzroy

W. C. Wilkins and M.

S. Kendrick

holder. Brace head.

Expanding and collapsing pianoforte case.

Railway carriage disconnecter
Fountain coffee-pot.
Dibbling instrument.

A moveable ash pan for fire places with parallel bars for separating the cinders from the ashes.

The Carcel spirit meteor lamp.

Spring for the runner of an umbrella or parasol. Watch protector.

ways.

THE ATMOSPHERIC RAILWAY SYSTEM.

There have been three experimental exhibitions during this week on a portion of the London and Epsom atmospheric railway, which has just been completed between the Dartmouth Arms and Croydon, and the success throughout has been complete.

First Day's Experiment.

The train consisted of ten carriages, (including that to which the piston is attached,) and its weight was upwards of 50 tons. Within a minute and a quarter of the piston entering the pipe, the speed attained against a strong head wind was at the rate of 12 miles an hour; in the next minute it rose to 18 miles an hour; and progressively increased to 25, 34, 40, and 52 miles an hour. The distance from the Dartmouth Arms to Croydon, five miles, was performed in eight minutes and three-quarters. The barometer in the piston carriage indicated a vacuum of 25 inches; and that in the engine-house, a vacuum of 28 inches.

Second Day's Experiment.

On one part of the journey this day we went a mile in 62 seconds, in an open carriage, without feeling any inconvenience. The Brighton railway is crossed by a viaduct, the ascent being with a gradient of 1 in 50, and in the middle of a curve of half-a-mile radius; up this incline (probably inaccessible to a locomotive engine from want of bite upon the rails) the trains went at full speed, the length of it being too short to affect the rate very sensibly, or make it necessary to apply extra power. The barometer ranged from 26 to 27 inches.

Third Day's Experiment.

On descending the viaduct towards Croydon, it appeared that the train would not be stopped in time by the mere application of breaks, and a valve in the piston was opened, which, allowing the air to rush into the vacuum in front, reduced the mercury in a moment from 27 inches to 12, and soon moderated the speed. The trains were 50 ton trains; when stopped at a station, two pairs of breaks were applied for about fiveeighths of a mile, and rather more than two minutes were lost by every stoppage, the train being at rest for a quarter of a minute.

At each station, Forest-hill, and Norwood, and Croydon, there are a pair of 50-horse power engines to exhaust the air, but at present it is not found necessary to work an engine at the middle station.

The engines have been built by Messrs.

287

Maudslay and Field, and are in every way worthy of the high reputation of their establishment for highly-finished and efficient workmanship.

ROTARY STEAM ENGINES.

The "satisfactory" Janus, (fitted with the Earl of Dundonald's rotary engine.)

The Janus, steam sloop, during the week, has been making experimental trips down the Medway. The first was made on the 11th instant, the Earl of Dundonald and Captain W. H. Shirreff, superintendent, being on board. From opposite the dockyard to Upnor Castle the wheels revolved about five times within the minute, when a breeze sprung up, and her canvass was spread. She then went down as far as Gillingham-reach, the wheels revolving about thirteen times within the minute. It now appears that after all the trouble and expense of taking her machinery to pieces and reconstructing it, there is not any alteration in the speed effected since her last experimental trip. The general opinion that prevails is, that this craft is a total failure. Chatham Correspondent of the Times.

The Novelty screw steamer, (fitted with Borrie's rotary engine.)

Malta, Sept. 24.

The Novelty, a steam bark, the first of a new line to run between Liverpool and Constantinople, arrived here from the former port late on the night of the 16th inst., after a passage of twenty days! She is commanded by Mr. Crowder, late of the Royal navy. This vessel is not only propelled by the screw, but is worked by a newly invented rotary engine, which the inventor expects will make a complete change in steam navigation. (?) The engine is two-thirds less in point of dimensions than an ordinary one of equal power, and its consumption of fuel is proportionately smaller. The entire weight of the machinery and boilers of the Novelty is only twenty-four tons. Her first attempt, however, must be considered a failure, as a heavily laden collier from Leith arrived here the same day, after a passage of twenty-four days.

We are informed that there are three more steam-boats in process of construction, at the present time, for the same company, to be built on the same principle as that of the Novelty, and that the result of the experiment is auxiously awaited. The Novelty proceeded on her voyage to Constantinople on the 18th inst.

1

Alexander Bain, of Hanover-street, Edinburgh," engineer, for improvements in electric clocks and telegraphs, part of which improvements are applicable to other purposes. September 25; six months. Alfred Vincent Newton, of Chancery-lane, mechanical draughtsman, for certain improvements in machinery for manufacturing screws. (Being a communication.) September 26; six months.

Alfred Vincent Newton, of Chancery-lane, mechanical draughtsman, for certain improvements in machinery for manufacturing metal pipes or tubes. (Being a communication.) September 26; six months.

John Reed Hill, of 28, Stamford street, Lambeth, civil engineer, for certain improvements in atmospheric propulsion, ap; licable to water as well as land carriage. (Being a communication.) October 2; six months.

George Roberts, of Wells-street, Cripplegate, miner, for certain improvements in the construction of lamps for illuminations. October 2; six months.

John Kershaw Ramsbottom, of Lancaster, cottonspinner, for certain improvements in machinery or apparatus used in the preparation of cotton, or other fibrous substances, for spinning. October 2; six months.

Frederick Rosenborg, of Kingston-upon-Hull, gentleman, and John Malam, of the same place, gas manufacturer, for certain improvements in or apparatus for watering or manuring and drying trees, plants, seeds, and roots, and for accelerating and improving the growth and produce of trees, plants, seeds, and roots, October 2: six months.

Alfred Hall, of Coxsackie, America, brickmaker, for certain improvements in machinery or apparatus for making, moulding, or manufacturing bricks, tiles, and other articles, from earthy or plastic materials. October 2; six months.

George Daniel Bishopp, of Egbaston, Warwick, civil engineer, for improvements in certain engines, or machines, used for obtaining mechanical power, and for raising and impelling fluids. October 2; six months.

Robert Clark, of Newburgh, ship painter, and Alexander Pirnie, of the same place, ship's smith, for certain improvements in steering vessels. October 2; six months.

John Simpson, of Langton Rectory, York, clerk, for certain improvements in obtaining and applying motive power. October 2; six months.

John Hale, of Leicester-square, Middlesex, Esq., for certain improvements in guns. October 2; six months.

Graziana Conté, of Regent-street, Middlesex, merchant, for improvements in machinery for cutting, carving, and sculpturing marble, stone, wood, and other like substances, being a communication. October 3; six months.

Moses Poole, London, gent., for improvements in rails for railways, being a communication. October 6; six months.

Gabriel Hippolyte Moreau, residing at 18, Boulevart Bonne Nouville, Paris, gent., for an improved steam carriage. October 6; six months.

Augustus Julien Van Oost, of Genbruge, near Ghent, but now of Osnaburg-street, Regents park, for improvements in treating seed, and in preparing materials used for fertilising land, and for aiding vegetation. October 6; six months.

Thomas Russell Crampton, of Southwarks-quare, Surrey, engineer, for improvements in locomoivee engines and railways. October 6; six months.

Thomas Howard, of the King and Queen Ironworks, Rotherhithe, Surrey, iron manufacturer, for improvements in rolling iron bars for suspension bridges and other purposes. October 6; six months. Joseph Quick, of Sumner-street, Southwark, engineer, for improvements in steam engines. October 9; six months.

John Lake, of Apsley, Herts, civil engineer, for certain improvements in propelling. October 9; six months.

Isaac Hartes, of Rosedale Abbey, York, farmer, for certain improvements in machines or machinery, for rowing, sowing, and manuring land. October 9; six months.

Edmund Morewood, of Thornbridge, Derby, merchant, and George Rogers, of Stearndale, gent., for improvements in the manufacture of iron into sheets, plates, or other forms, in coating iron, and in preparing iron for coating and other purposes. October 9; six months.

Alexander Parkes, of Birmingham, artist, for improvements in coating or covering certain metals with other metals, and metallic alloys, and for ornamenting the surface of various metallic articles. October 9; six months.

Thomas Wood Gray, of Workworth-terrace, Com mercial-road, plumber, for improvements in ports and apparatus for opening and closing ports of ships, or other vessels, also applicable in opening and closing windows and other instruments having the like movements. October 9; six months.

⚫ Henry Francis, of Wardour-street, civil engineer, for improvements in the manufacture of gas. Oct. 9; six months.

Edward Morgan, of Tenby, Pembroke, gent., for an improved envelope for letters. October 9; six months.

Edward Patrick Emerson, of the city of Dublin, doctor of medicine, for improvements in the manufacture of paints, pigments, cements, and other plastic compositions, and in the machinery or apparatus to be used in such manufacture, parts of which improvements are also applicable to the manufacture of artificial stone and marble. October 9; six months.

Thomas Holingsworth, of Birmingham, cigar merchant, for a certain improvement or improvements in the construction of cases for holding cigars. October 9; six months.

Joseph Edward Judson, of Ashton-under-Lyne, Lancaster, saddler, and Edward Banton, of Walsall, Stafford, commercial traveller, for a certain improvement, or certain improvements in covering rollers used in spinning cotton and other threads, also in covering mill straps. October 9; six months.

David Wilkinson, of Potters' Pury, near StoneyStratford, gentleman, for improvements in obtaining motive power. October 10; six months.

Edward Lesley Walker, of Foley-place, professor of music, for improvements in pianofortes. October 10; six months.

Joseph Clishild Daniell, of Tiverton mills, near Bath, for improvements in dressing and finishing woollen and other cloths. October 10; six months.

George Fergusson Wilson, of Belmont, Vauxhall, gentleman, George Gwynne, of Putney, gentleman, and James Pillans Wilson, of Belmont aforesaid, gentleman, for improvements in the manufacture of soap. October 10; six months.

Alexander Jamieson, and John Frederick Lundholm, of Tothill-street, Westminster, manufacturing chemist, for improvements in dressing ores requiring washing. October 10; six months.

John Whitehead, of Leeds, for improvements in machinery for combing, hackling, and straightening wool, flax, tow, and other fibrous suistances. October 10: six months.

[For continuation see cover of Monthly Parl.]

Errata. In the account of the experiments with the Bee, given in our last Number, p. 270, for "to ensure more blowing off," first col., line 9 from the bottom, read "to ensure none blowing off;" and for "the paddles were dismounted," read "the paddles were disconnected."