AMERICAN MECHANICS' MAGAZINE, Museum, Register, Journal, and Gazette. SIR, I have taken the liberty of both sides of the wheel, into which are insubmitting to your notice, and to that troduced brass cases, well fitted and secuof your able Correspondents, a rough red, for brass cocks to move in. The arms sketch and description of a Steam- of the wheel are hollow also, and into each and-Water-Wheel, which I have is a separate opening, as at a a, communihad in contemplation many years. Description. Fig. 1 is a side-view of the wheel, the rim of which is hollow; at equal distances, marked oo 0, are openings through cating with the rim; the circular part, bb, is turned true on the face; at C is a perforation through the axis, the other end of which works in a stuffing-box at D, fig. 2, within the condenser. Fig. 3 is a strong brass washer, turned true on the face and edge; at E there is an opening 386 STEAM-AND-WATER-WHEEL. quite through; the space marked at F a hoop-plate round the box, G, by screws is only an indentded archway, through through the flanch on the box, to secure which (when the washer is brought against the face air-tight. At fig. 4 are the handthe face of the wheel to the corresponding dotted spaces and letters) the steam escapes into the condenser. The round metal box, G, fig. 2, is turned true on the inside, and inte it is introduced the above washer, which is closed against the face of the wheel by screws through the back side of the box, communicating with the boiler by pipe P. At RR are flanches on the box, G, and also on the wheel, at I; into a recess, against the wheel, a skin is pressed by geering. Instead of water, I propose ma- The operation is as follows:-Suppo- is now a vacuum formed in the top of the sing the machine to have been at work, wheel; close the cocks at Y, fig. 4, and all the cocks would be shut on the rising side, which must now be opened; slide back the guide-plate at Y, fig. 4, and open the cocks, and the whole space on the top of the wheel above the fluid, marked by a dotted line, LL, fig. 1, will be open: put on the steam, and open the cocks on the edge of the wheel, to let out the air; close the cocks, and condense the steam. There adjust the guide-plate; again put on the steam, and the fluid will rise in the wheel in the direction shown by the arrows; open the condenser and take off the brake; the steam will now press the fluid in succession into the vacant spaces in the top part of the wheel, where a vacuum is regularly forming, as they pass the opening to the condenser on the rising side. I conceive WEIGHTS AND MEASURES. "Take a pendulum which will vibrate seconds in London, on a level of the sea in a vacuum; divide all that part thereof which lies between the axis of suspension and the centre of oscillation into 391 393 equal parts; then will ten thousand of these parts be an imperial inch, twelve whereof make a foot, and thirty six whereof make a yard. temperature, will be a gallon, which gallon will contain two hundred and seventy-seven cubic inches, and two sandth parts of another cubic inch." hundred and seventy-four one-thouLond. Mec. Mag. WOOD LIES UNDER WATER. Take two pieces of wood, planed perfectly smooth, so that no water "Take a cube of one such inch of can get between them when their distilled water, at 62° of temperature smooth surfaces are put together:by Fahrenheit's thermometer; let cement one of the pieces to the botthis be weighed by any weight, and tom of a glass vessel, so as to have let such weight be divided into 252. its smooth side uppermost; then place 468 equal parts; then will one thou- the other piece above it, and hold it sand of such parts be a Troy grain, in this situation till the vessel is filled and seven thousand of these grains with water, and it will be found to lie will be a pound of avoirdupois, the at the bottom as quietly and firmly operation having been performed in as if it were a piece of lead or air Ten pounds such as those men- stone. London Chemist. tioned of distilled water, at 62° of SIR, A Correspondent asks for a "Plan and Description of a Portable Hand-Mill. I beg leave to forward one, which is very simple in its construction, and not likely to be injured in travelling. I have had an opportunity of seeing it used with success for several years without requiring any repair. Your Correspondent desires that it might take up but little room; this, however, is hardly to be expected without a considerable augmentation of labour in grinding, as the only part that could be dispensed with is the wheel, instead of which a second handle might be substituted precisely similar to that marked C. Description. PEWTERER'S SOLDERING FURNACE. The Pewterers have long been in the habit of employing a blast of hot air, for the purpose of heating and soldering the various parts of their articles together with soft solder, and with very great convenience indeed; the blast of air being quite clean, and not discolouring the parts with smoke, soot, &c. Fig.1. represents a side elevation; Fig. 2, a front elevation of the mill; a is an upright, to which the body, b, of the mill is fixed by means of the screw-bolts, hhh; e; a handle attached to the spindle, d, which passes through the body of the mill; e, another handle fixed to the wheel, f, which revolves on the extremity of the spindle, and serves to facilitate the turning of the mill; g, the hopper; I the The small furnace employed for valve; m, a small door, for the purpose of this purpose is of a round or oval WHITENING RRASS WORK, &c. shape, and is formed of an exterior case of sheet or cast iron, lined with fire-bricks or tiles and clay. It is fed with charcoal, and the air from a 389 insertion of which you will greatly Your obedient servant, pair of bellows is made to enter by Richmond-street, Wolcot-place,} an iron pipe on one side of it, so as to pass through the burning coals, and to escape through another iron pipe, on the opposite side, above, in the heated state. The parts to be soldered, having a little oil previously applied to them, are to be held in the steam or hot air, until they become hot enough to melt a thin slip of soft solder held to them, which flows between, and unites the parts firmly together. The fusibility both of the pewter and of the solder is so nearly alike, that a very little excess of heat would melt the pewter articles, and workmen are, accordingly, sometimes obliged to wet them instantly on the solder flowing, in order to prevent that mischief. This ingenious contrivance is, no doubt, capable of being used for many other purposes; and, indeed, a very valuable application of a stream of hot air has been lately made by Mr. Bryan Donkin, civil engineer, who has taken out a patent for dressing net-lace, &c. by means of it. Lond. Mec. Mag. WHITENING BRASS WORK. Brass work boiled with tin shavings, a few grains of tartaric acid, and an equal quantity of orgal with soft spring water, in a brass kettle, will become white. The brass should be kept covered with water, and suffered to boil about half an hour, till the colour required is obtained, and then immersed in cold water immediately, and washed off. The solution will be good for three or four times, by adding each time a little more of the acid, but is highly poisonous. Lond. Mec. Mag. SQUARING NUMBERS. SIR, Observing in your valuable Work, a short method of Squaring any given Number, I have taken the liberty of sending you another, by the Lambeth. I have taken the same example, 47653843 16. . 609 5676. 285009 7624544 38123056 285923049 2270888752668649 Observe, the first figure is squared ;then the second line is found by squaring the next figure, and multiplying all the remaining figures to the left of it by its double. Each figure is removed two places towards the right hand. Example.-4x4=16, first line. 7X7-49; set down 9, and carry 4.The double of 7 is 14. 14X4+4-60; set down 60, which is equal to 009, second line. Third line: 6 times 6=36; set down 6 and carry 3; then twice 6 is 12; 47×12+ 3=5676; and so on till the end. Lond. Mec. Mag. SELF-REGULATING PENDULUM. SIR, I am induced to lay before you the particulars of an invention, I believe an original one in its conception and application, simple in its principle of operation, and effective in producing the very important and desirable object of attainment to the scientific world, an accurately SelfRegulating Pendulum. If I am in error upon the subject of its originality, it will give me pleasure to be set right by any of your better informed Correspondents, who will state the particulars of any published invention similar in principle and application to mine. Prefixed, I send you an outline, indicating the parts with sufficient precision, I believe; but not being a |