"A Weaver,” as he signs himself, in Wood-street, relative to my patent Throwing Machinery; and although I should feel a much greater satisfaction in replying to such kind of queries, were they authenticated by the proper signature of the writer, yet, as it will not occupy much time in answering them, I will endeavour to set your Correspondent at rest in as few words as possible. in has for years been gradually improved upon, and a most fascinating model of which has been exhibited, for Heaven knows how long, in the Tower of London, ou dro 21:1990 "There is, however, one puzzling query still remaining unanswered, which I conceive your Correspondent intended as a regular poser. How do I calculate the velocity of my spindles?" I must confess, that not feeling myself quite competent to answer this question, I most unwillingly throw myself on the mercy of your nume rous readers, sincerely hoping that some one will be kind enough to gratify your Correspondent by a sofution of this important question, and at the same time assist me in so extraordinary a dilemmableiv ISTIBO I have the honour to be, Siriqzs ་་ Very faithfully yours, to FROM 9: RICHARD BADNALLY JUN! It is perfectly evident, from his own statement, that he is not very intimately acquainted with either silk, wool, or cotton machinery, otherwise he would know that from one to three thousand revolutions of the spinning spindle per minute are butForm a common speed; and that in certain manufactories in different parts of England, that speed is increased to from four to six thousand revolutions; and I believe there are instances in cotton-spinning where the number of revolutions per minute considerably exceed even that. The allusion your Correspondent makes to my reply to a letter which some time ago appeared in your Magazine, I shall pass over by merely remarking, that I am not in the habit of making statements which I cannot thoroughly substantiate; and that whatever may be the opinion of either him or his friends as to the impracticability of such statements, I should in future strongly recommend their being perfectly certain of p. such impracticability before they ventured to publish any decided sentiments on the subject. As to the remark of your Correspondent, that the general opinion of the silk trade is adverse to my patent, time alone c can determine how far it is so on this point I am perfectly easy. The Weaver in Wood-street is likewise very much out of his mark when he supposes that my spindles are driven by toothed wheels; and the publication he has given to this error convinces me that he is as per fectly ignorant of the nature of my Throwing Machinery, as he is of any other, unless it be the wooden crawling mass of cumbrous matter which his friends have described to him; which,eren through France and Italy, P.S. Your Correspondent may probably be more inclined than ever to doubt the accuracy of my asser tions, when I assure him that I show him the bobbins upon silkwinding engines revolving at greater speed than the limit he assigns to that of Throwing Machinery, bm dolendol si no eldst såT REPLY TO A LETTER ADDRESSED TO SIR,-In your valuable Magazine, "The Damascus barrels having little REPLIES BY W. E. WIGHTMAN, ON GUNNERY. or no expansibility when fired, do, in consequence, require to be bored perfectly cylindrical. The charge, when propelled from such barrels, meeting with no irregular resistance or strait places, occasions but little recoil, while the Stubbs-twisted, on account of their flexibility, require to be bored wider at the breech, that the shot may be partially delayed, by being driven into the straiter part of the barrel, that it may receive the full strength of the powder. The intention of boring guns in this manner is to counterbalance the expansion during the discharge; for, as I previously observed, the shot could not be dislodged with equal force when the barrel yields to the expansion of the exploded powder. The consequence of boring guns in this manner cannot but be understood by the most uncircumspect observer; for the necessary dilatation of the barrel during the passage of the charge through the straiter part, distends the fibres of the metal to a degree which their elasticity cannot always recover; and hence follow the repeated burstings of guns by a small addition to the regular charge. The Table on the Cohesion and Strength of Metals, vol. 1. p. 71, of your Magazine, would have saved Or (had he seen it) such futile expressions as those regarding welded needles, hoop-iron, cast iron, and brass and with respect to a succeeding remark of his on the strength of barrels, where he says, "I do not see why a barrel should shoot the better for being thick; that is, a barrel as thin as writing-paper should shoot as well as a barrel half an inch thick, provided the force of the powder do not make any permanent alteration in the size of the bore." Let me ask him, if any barrel were subject to this permanent alteration, every time the gun was fired, how many shots he W.E. WIGHTMAN cei 9269 ai jos hoo77 1978917 SHI REPLY TO HAMMER, vodil big Page 132, Vol. IV. od od SIR, IN reply to Hammer," 1 must say that the best method of removing the tead from gun-barrels, is to subject it to the boring bench of a good workman; for he can so pack the boring bit as to bore out the lead without touching the iron; but when that cannot be done, a fine steel wire $270 PERPETUAL MOTION ON PHILOSOPHICAL PRINCIPLES. brush, which most gun-makers send either with the ramrod or washrod, will answer the purpose tolerably well. By using it constantly, the gun will be prevented leading at all. But it must be observed, that, previous to the use of the brush, the touchhole should be closed, and the barrel filled with boiling water, which softens the adhesive powder, and partially assists in cementing the lead to the barrel. The barrel should afterwards be washed in cold water, for the steam from hot enters the pores of the iron, and will not, from its confined situation, evaporate for some time. "Hammer" will find a proof of the comparative merits of the Flint and Percussion Guns in the same page with his communication. I am, &c. &c. I a W.E. WIGTHMAN. The power is at present applied to the machinery of a clock; this clock, unconnected with the power, is calculated to go for two years without winding up, by the weight of a single pound, that gives motion to a pendulum of twenty pounds, which moves through a space of 518-400 inches in 24 hours, while the small maintaining weight (a single pound) descends only 1-10th of an inch. The internal work of the clock consists of three wheels. In order that the superiority of this movement may be obvious to every understanding, as well as to those more conversant with the more difficult parts of mechanics, it is necessary to mention, that the co common eight-day clock requires a weight of fourteen pounds, where this only requirs a weight of one, is wound up once in eight days, and moves a pendulum of three pounds and a half, when this moves one of twenty, and is wound up only once in two years. In twenty-four hours the maintaining weight of the common clock descends six inches; in this it descends only 1-10th of an inch. The least weight which we at present recollect to have heard of being used by the first artist of London is five or six pounds, where this requires only one, in consequence of the diminution of friction. So far it has been thought necessary to describe this clock in comparison with the common one. "We now come to that part to which extraordinary merit is to be ascribed the faculty of winding itself up without the intervention of human power. This faculty is derived from the weight of the atmosphere, and can never cease (under the conditions after mentioned) while the machine lasts, and while a column of air either loses or gains 1-150th part of common its of eight five times in the space years, the time which the clock goes without requiring any assistance ; or, in other words, as long as the change of the weight of the air, five times in the space of two years, shall be such as to cause the mercury either to ascend or fall 2-10ths of an inch in the barometer above or below its mean 1 height. The wearing out of wheels, or of any kind of machinery by friction, never can be avoided; accordingly, it has never been required in the discovery of a perpetual motion. It is therefore sufficient, on that subject, to say, that the present machine, upon a fair comparison of its friction with that of the common clock, would probably move five centuries, a period sufficient for any purpose that can be required." 433METHOD OF BANDING SPINDLES, ETC. I am certainly of opinion, that Mr. Scheffer's plan of inflating his machine with air instead of employing cork, is decidedly superior, not only on account of the greater buoyancy obtained, but from its being thereby rendered more portable, as it can, when wanted, be inflated for use in the twinkling of an eye Fors the information of metchanics, I will, with your permission, describe a simple method of -constructing a Marine Cravat," not only much cheaper, but equally efficacious with that of Mr. J. H. Bell of Procure at any butcher's a bullock's weasand for 4d., which inflate with air then with a piece of sail-twine divide it into four or five compartments, like a string of sauhsages, to enable it to take a circular anoiiboo adiabat, 66 271 form; tie this round your neck, and 2, T. BELL. Commercial-row, Whitechapel. te METHOD OF BANDING SPINDLES UPON AN OLD, BUT at ni mit wit ALMOST FORGOTTEN PRINCIPLE. 2691 Place a pulley at one end of the frame betwixt the roller and the spindles, then pass the band through the pulley and round the spindle, from whence it must be passed on to the Toler, and from thence to the spindle, so on in succession until it comes to the other end of the frame, where another pulley must be fixed, and through which the band must be passed and carried betwixt the roller and the spindles to the first pulley, where the ends of the band are to be joined togeJither! I 28 15 N. B.Although, by this method, any number of spindles may be banded together, it would, perhaps, be advisable not to exceed twenty. Description. A, the spindles., BB, the pulleys, fixed at each end of the frame. CC, the roller. D, a pulley to support the band, the band going under the roller. SAMUEL SMITH, Smedley, near Manchester, 272 NEW PATENTS-CORRESPONDENCE, ETC. A new Fire-engine has been invented at Berne, by a mechanic named Schenk, which possesses much greater facility than any former machine of the same description. Its force is said to be so extraordinary, that the column of water which it sends out will, at the distance of 100 feet, easily break up the pave ment of the street, untile the houses, and demolish their masonry up to the second floor. MACHINE FOR UPROOTING TREES. A Toronto farmer says, in a letter to an American Paper, that he had "just seen a Machine for pulling up the Stumps of Trees, invented by a Mr. Harris, an ingenious mechanic, which is extremely powerful, multiplying the force applied to it 700 or 800 times, which also can be increased or diminished as occasion may require. It is capable of pulling out the largest stumps, and can be moved from place to place by a single yoke of oxen; it is, withal, very simple, and may be worked by either men or horses. machine will, when delivered and erected, cost about 25 dollars." The TO PREVENT MISCHIEF BY ROOKS. Take a straw-rope, such as is used in some counties for thatching, and stretch it across the field from about the middle towards the fences, supported by stakes fixed in the ground, to raise it a few feet. This is a sufficient notice to the rooks to keep off. If fields are large, other ropes may be placed at a proper distance; for if food grows scarce, they may, after cautiously reconnoitering for some time, approach to within 200 or 300 yards of the supposed trap. quetry, and other fire-arms. Communicated to him by a certain foreigner residing abroad.-Dated April 23, 1825. Thomas Alexander Roberts, of Monford-place, Kennington-green, gentleman; for a method of preserving potaDated April 23, 1825. toes and certain other vegetables. Samuel Ryder, of No. 40, Gowerplace, Euston-square, coachmaker; for an improvement in carriages, by affixing the pole to the carriage by a newinvented apparatus.-Dated April 28, 1825. Daniel Dunn, of King's-row, Pentonville, manufacturer of essence of coffee and spices; for an improved apparatus for the purpose of beneficially separating the infusion of tea or coffee from its grounds or dregs. Dated April 30, 1825. distiller; for an improved safe to be James Fox, of Plymouth, rectifying used in the distillation of ardent spirits. -Dated May 14, 1825, TO CORRESPONDENTS. If J. B. C. D. has really made the discovery he speaks of, there is no doubt he may obtain both profit and honour by it. We would recommend him to apply to the Commissioners of Weights and Measures. Anti-Hippopotamus would be much obliged to Mr. Thomas H. Bell, if he would inform him how to mount his Water-horse without capsizing it? Communications received from-Felix D. D. E.-Plane-J. Walker-TaperP. Smith-Dick Forge-Samuel Smith— Ikey Pringle-Timotheus-R. W.-D.— A. R. F.-A Reader in the Potteries-A Seaman. Advertisements for the Covers of our Monthly Parts must be sent in to our Publishers before the 20th day of each Month. NEW PATENTS. Augustin Louis Hunout, of Brewerstreet, Golden-square, gentleman; for certain improvements in artillery, mus Communications (post paid) to be addressed to |