30 CAPTAIN MANBY'S PLAN FOR THE SPEEDY EXTINCTION OF FIRES. The cart contains six engines each, charged with the impregnated solution of an ingredient best adapted to extinguish fire. When the first engine has expended its store of antiphlogistic fluid, a supply of others in succession may keep up a constant discharge, until regular engines and plenty of assistance arrive, should the fire not be entirely subdued by these first efforts. When a small quantity of simple water is cast on materials in a state of violent combustion, it evaporates into steam from the heat, and the materials thus extinguished readily ignite again; the addition of incombustible ingredients, consequently, becomes necessary to make quality supply the place of quantity, and thus with the smallest portion prevent the fire rekindling. To give the most extinguishing properties to common water has engaged the experimental attention of many, in different countries, and it has been rendered by *1734. M. Fuches, a German physician, by throwing balls into the fire, containing certain preparations, which burst with violence, instantly quenched the fire. 1761. Zachary Grey used the same process, in which were alum, sal ammoniac, and other saline matters, with water. In the same year Dr. Godfrey, in a public exhibition in a house erected for that purpose near Mary-le-bone, applied the like ingredients with great success, by the action of confined gunpowder only, which, exploding, dispersed the solution on the materials in combustion, and effectively extinguished the same. 1792. M. Van Ahen, at Stockholm, made numerous public experiments to show the effects of several combined ingredients to render materials entirely incombustible; he is stated to have subdued an artificial fire by two men and forty measures of preparation, that would have required twenty men and 1500 of the same measures of simple water. In the same year, M. Nil. Moshein made many public exhibitions to confirm that com them more effective to extinguish fire than forty times the same quantity of common water (a circumstance not speculative, but confirmed by trial made upon buildings erected for that purpose ;) but the simple ingredient of pearl ash dissolved in water, when applied on burning substances, forming an incrustation over the surface extinguished, and thereby preventing the access, has in my estimation, a decided preference; it has likewise the superior recommendation of the readiness with which any person may imbue the water with it, while the compounds cannot be had but at considerable cost, nor be prepared without labour and nice accuracy in their respective proportions. Thus, at the moderate ratio of twenty times increasing the quality, the cart would convey an extinguishing fluid equal to one tun and a half of common water. Specification in reference to the Apparatus be longing to the Fire Cart. Each machine is a strong copper vessel, of a cylindrical form, two feet in length, and eight inches in diameter, capable of containing four gallons: a tube of the same metal, of one-fourth of an inch in diameter, curved so that its end is carried to the side of the vessel, with a stop-cock and jet-pipe, the vent of which is one-eight of an inch in diameter at its top, reaches to within half an inch of the bottom, and is to be screwed so closely into the neck of the vessel as to preclude the possibility of the escape of the air. Three gallons of water, holding in solution any ingredients* best adapted to extinguish fire, are to be put into the vessel, and then the room remaining for the fourth gallon to be filled with closely condensed air; to effect which, the jet-pipe is to be unscrew bustible meterial might be made perfectly incombustible; as also did Mr. W. Knox, of Gottenburg. * Pearl ash, dissolved in water, when applied on burning substances, forms an incrustation over the surface extinguished, and prevents that part from reinflaming. BROWN'S GAS ENGINE-CLOCK-MAKING. ed, the condensing-syringe fixed in its place, and the air to be pumped in, to the utmost power of the strength of the vessel to contain it; the stop-cock is then to be closed, condensing-syringe taken off, and the jetpipe replaced. On turning back the stop-cock, the condensed air re-acts on the water, and casts it to a height proportioned to the degree of condensation. That the machine may be more easily carried, where access is difficult, it is put into a leathern case with a strap, and slung over the shoulders of the bearer, is thus conveyed easily, and then directed with the utmost precision to the point requiring the water. As directions for the effective arrangement of fire carts in populous places, the following plan I should propose: That at each watch-house, from the time of the watch setting, there should be in attendance a regular fireman, instructed in the use and management of the apparatus; and that each parish should be provided with one or more fire carts, according to its extent or number of wards, and the vessels or engines composing the complement of the carts to be kept charged ready for being immediately applied. When watch-boxes or stations are at a considerable distance from the watch-house some central watch-box should have a single engine lodged ready for application, to be brought on the alarm by the watchman, and delivered to the fireman, who repairs to the spot on the alarm of fire being given, with as much expedition as possible. Should the fire have broken out near the depôt of the fire cart, the fireman in attendance will take the cart with him, or an engine from it ready to apply; if otherwise, the watchmen will each bring an engine, which the firemen will expend, and by receiving from others their engines, a regularly-continued and well-directed stream will be kept up, which, from the early opposition to the fire, will no doubt check the flames, if not entirely subdue the fire; should the distance be considerable, the fireman, aided by a watchman, would convey the cart to a place on fire with as much despatch as possible. 31 I therefore cannot be deceived. The fire, when I first saw it, was just caught, and Í conceive was quite extinguishable by your machine for at least twenty minutes. "I may also here give my opinion as a naval man, as to its great use, in my opinion, on board ships, in case of fire below, where water is not easily conveyed. I shall never go to sea again without one of them for the use of the store-rooms, &c. Upon the whole, I do declare to you, it is, in my opinioh, one of the best inventions I ever saw; and wishing you every success in the prosecution of your generous plans, "I am, Sir, yours, &c. "P. B. PELLEW." BROWN'S GAS ENGINE. SIR, Mr. Brown's contrivance is not new. There is, at present, in Mr. Leslie's Class-room, College of Edinburgh, a machine constructed upon the very same principles; the primum mobile being an oil lamp, which rarifies the air, thus forming a kind of vacuum under a piston, from which the power proceeds. This is an incontrovertible fact, for I have seen the machine in full action. It moves with prodigious velocity, so long as the cylinder, in which the piston acts, is cool; but as soon as it becomes heated, the process of the machine is greatly retarded. This is not the first time that ingenious men have been found asserting their contrivances to be new inventions. The late Mr. Bramah went into the same mistake, when he pronounced his hydraulic press to be a new mechanic power. CLOCK-MAKING. J. Y. SIR,-In perusing your 48th Number of the "Mechanics' Magazine," page 315, I observed some remarks by Mr. James Collins, on Dr. Franklin and Mr. James Ferguson's three wheel clocks, with his own improvement. I perfectly agree with Mr. Collins in his objections, but see farther room for improvement in Mr. Fer guson's, than what Mr. Collins has point. ed out. In 1817, I made one with three wheels inside, but added two under the dial, to carry the hands direct: that is, the hour and minute hands only. It goes Letter from the Hon. Capt. Pellew, R. N. to eight days, with a fall of twenty-one Captain Manby. London, June 27, 1816. "MY DEAR SIR,--Having been one of those who witnessed, with much satisfaction, the trial of your newly-invented machine for the extinction of fire in its earliest stages, I cannot refrain from relating to you, that, in the late fire close to my house, and which I myself discovered, if I had had one of the machines at my immediate command, I do not hesitate to say, I could have saved the whole premises and an uninsured property of nearly 12,0001. I can venture to assert this fact, because it came under my own inspection; inches, and goes as correct as it is possible for any plain timepiece to do. In 1820, I made another with three wheels only. The hands are fixed on their own centres or axes, and go direct, but require to be set right separately. This clock goes eight days, with a fall of twenty-one inches. I am, Sir, &c. Newcastle-upon-Tyne. G. S. [A more detailed description of our Correspondent's Clocks would be acceptable.-ED.] 32 ers. FRUIT-GATHERER-MACHINES FOR RAISING STONES. FRUIT-GATHERER scription of the machine invented by Mr. Richardson, of Keswick, for raising stones, in the 8th Number of in which the firm retention of the cylindrical plug is satisfactorily attributed to the elastic power of the stone, I have seen four or five men, with a common triangle, and double and single block tackle (without a roller and levers,) raise a stone of nearly two tons weight, although the plug was not driven into the hole more than three-quarters of an inch. I apprehend, that the inferior elasticity of Portland and other soft stones would render the application of the machine uncertain in its effect, and extremely hazardous. Bridport. I am, Sir, &c. TO OUR E. N. READERS AND CORRESPONDENTS. To the use of the Sliding Rule, we shall shortly devote a few pages. SIR, A year or two ago, as I passed through the town of Carlsruhe in Germany, I saw a machine the Edinburgh Philosophical Journal, for gathering fruit from the pendant branches of trees incapable of supporting a ladder, and out of the reach of the hand, which struck me as being both simple and well adapted to the purpose. Should it be considered so by you, and as worth the insertion in your valuable Magazine, the enclosed sketch of it is at your service. The season for putting it in use is now at hand, and possibly it may be turned to some effect by one or other of your numerous readThe construction of it is this; A piece of flat, light board, about eight inches over, and, if you please, somewhat more in length, of either a round or an oval form, has a row of holes bored all round it near its edge, taking the shape of the board, and about the diameter of a quarter of an inch, into which are driven tight as many pegs, about six inches in length, which pegs are then bound together by a neat platting or banding of basket-work, about the breadth of a third of the height of the pegs, and worked down close to the bottom of the board. The part of the pegs above the wicker-work is to be cut "tooth fashion," for being applied to the stalk, between the fruit and the bearing spur of the tree, and by a wring of the machine, to draw it off into its interior. This head, if I may so express it, is attached to a light pole, of any convenient length for the purpose. The only improvement I would suggest is, that the bottom should be, in a great measure, cut out, and supplied by a coarse netted bag, which might remedy the chance of the fruit's rolling out, or of its getting bruised by falling on the board. It is possible that this contrivance may be in use in the apple districts of this country, but I have never met with it. We shall be glad to hear again from Mr. T. S. D. of Bath. Communications received from E. Nicho letts-J. M'Vey-J. J. Dartford-E. N.- MECHANICS' MAGAZINE. ing a greater quantity of original contribu- This work will be published every Satur day in a pamphlet of sixteen octavo pages, containing several fine wood engravings, subscriptions $4 per anum, half payable on delivery of the fourth number, the remainder on delivery of the 26th number: J. V. SEAMAN. 221 Broadway. MECHANICS' MAGAZINE, Museum, Register, Journal and Gazette. No. 3. AM. ED.] "The most valuable gift which the Hand of Science has ever SATURDAY, FEBRUARY 19, 1825. [Price $4 PER ANN. "Theoretical and practical men will most effectually promote their mutual interests, nor by affecting to despise each other, but by blending their efforts; and an essential service will be done to mechanical science, by endeavouring to make all the scattered rays of light they have separately thrown upon this region of human knowledge converge to one point."- -Dr. Olinthus Gregory. ILLUSTRATIONS OF THE MARQUIS OF dispatches over great distances in a WORCESTER'S CENTURY OF INVEN- short time? and TIONS. No. 7. The universal telegraph, for day and night signals, invented by No. 4. The sort of cipher here re- Lieutenant-Colonel Pasley, of the ferred to was the subject of much Royal Engineers ?-S. R. conjectural speculation (see Gent.'s Nos. 9, 10, and 11, point evidently Mag. vol xviii. p 55) till the inge to the invention of the torpedo nious writer of the article Cipher, The following account of its appliin Rees's Cyclopædia, discovered, cation, in modern times, is taken among the Harleian MSS, a paper from the "National Register," Enin the hand writing of the Marquis glish newspaper, of the 12th Sepof Worcester, which is supposed to tember, 1813. The invention is contain a full specification of the American, and the account also Ameinvention. It is entitled "An Expl- rican. It may, perhaps, be in the nation of the most exact and most recollection of some of your readers, compendious Way of Short Writing; that, some little time previous to the and an Example, given by way of event here recorded, a similar attack Questions and Resolves upon each was made on his Majesty's ship Rasignificant Point, proving how and milies, and that, after two or three why it stands for such and such a unsuccessful attempts, the Americans Letter, in order alphabetically placed succeeded in attaching the machines, in every page.' His method of which, as soon as the operator had writing may be thus explained: an taken his departure, blew up with engraved page is given to write upon, tremendous force. The effect proin which are made horizontal rows duced was the destruction of almost of octangular squares or chequers; the whole fore part of the ship, part and a straight line is to be drawn of the cutwater being carryed away. from the centre towards the circum- The tide was then very unfavourable ference of these squares, in different to the attempt, and prevented the positions and of various lengths, for machine being fixed so as to do more each letter of the alphabet. Thus, mischief. I speak of this, however, A is a short horizontal stroke made from recollection only. to the right hand, and not touching the circumference; I is the same stroke, passing close to the circum"Mr. E. Mix, of the navy, a gentleman ference; R is the same stroke, going of integrity and enterprise, has been for beyond the circumference ; E, N, and several weeks preparing torpedoes to atW, are represented by a similar stroke tempt the explosion of the enemy's shipin the opposite direction, but varying gun ship, Plantagenet, that has for a month ping in Lynn Haven Bay. The British 74in their lengths. By a like method, past been lying abreast of Cape Henry he suggests that we may write with light-house, and has rarely had the compaa dot, or single point only; which is ny of any other vessel, appeared to Mr. Mix to be placed at a certain distance, experiment on. Accordingly, on the night as the most favourable object for trying his and in a certain direction, from the of the 16th of July, accompanied by Capt. centre of the octagon, for each letter Bowman, of the Salem, and Midshipman who of the alphabet. The Marquis pro- M'Gowan, of the United States navy, poses this contrivance for the pur- whole enterprise, he left his place of renvolunteered their assistance during the pose of writing with secrecy as well dezvous, and proceeded down to the Planas with brevity, and leaves it to the tagenet, of 74 guns, in a large open boat, will of any person to change the va- which he calls the "Chesapeak's Revenge," lue or name of the letters as may difficulty in ascertaining the position of the and, from previous observations, found no suit his fancy or intention.--Vide ship. When he had got within forty faRees's Cyclopædia, article Cipher; thoms of her, he dropped the torpedo over, where a specimen of the Marquis's in the very instant of doing which he was invention is given. hailed by one of the enemy's guard-boats; the machine was speedily taken into the No. 6. Does not this suggest the boat again, and he made his way off in safeidea of the telegraph for conveying ty. On the night of the 19th Ire made an "Norfolk, July 27th. |