On the Horticultural Management of the Sweet or Spanish 156 157 The Bakerian Lecture. An Account of some new and analytical Researches on the Nature of certain Bodies, particularly the Alkalies, Phosphorus, Sulphur, Carbonaceous Matter, and the Acids hitherto undecompounded; with some general Ob- servations on Chemical Theory. By HUMPHRY DAVY, Esq. Sec. R. S. F. R. S. Ed. and M. R. I. A. Method of preventing Doors from dragging on Carpets. By Apparatus for making Carbonated Hydrogen Gas from Pit Coal, and lighting Factories therewith. By Mr. SAMUEL CLEGG, Description of a Crank useful in working Telegraphs. By Mr. Papers translated from Foreign Works. - Extract of a Memoir on the Analysis of several Marsh Iron Ores On the Action of Nitric Acid upon Cork. By Mr. CHEVRUEL, 110 Researches on the Means of ascertaining the Proportions of Acid and Potash that enter into the Compositions of Sulphate of --- Experiments on Sulphur, and its Decomposition. By M. Description of a Process employed for determining the Exist- ence of Alumine in the meteoric Stones. By B. G. SAGE, Observations and Experiments on the Nature of some newly dis- covered Properties in Alkaline Metals. By M. CURAUDAU, Description of a Process by which Potash and Soda may be re- duced to the Metallic State without the Concurrence of Iron. On oxymuriatic Acid. By M, JOSEPH MOJON, Experiments upon tartarous Acid, and particularly upon the Acid which it yields on Distillation. By MM. FOURCROY and On common Opium, and on that extracted from the Papaver Somniferum of Linné, cultivated in France. By M. ACCARIE, 296 Chemical Experiments upon Indigo. By M. Chévreul, Experiments and Observations made by M. Ritter, of Munich, on the Production of Metalloids from Potash and Soda, as announced by Mr. Davy, collected from M. Ritter's Letters in the Course of February 1808. By M. WEISS, On the Conversion of Malt Spirits into Vinegar; and on the Red Patents granted for Inventions in the Months of April, May, PLATES PLATES IN THE FIFTEENTH VOLUME, SECOND SERIES. To face Page 1. Windlass, Windlass Bitts, and metallic Hawse-hole Chamber, - 3. Instrument for stabbing Cattle, Swivel-headed Churn Staff, 8 16 40 72 104 9. Penna-polygraph or Pen and Stylographic manifold Writer, 200 10. Improvements on the Wheel and Swing Plough, 208 ་ 11. Method of preventing Doors from dragging on Carpets, and 236 12. Engine for cutting Hay and Straw into Chaff, 264 13. Street-Lamp, Burner, and Lantern Head, and Improvement ib. 14. Apparatus for making Carbonated Hydrogen Gas from Pit Coal, 15. Improvement in a rotative Engine, 16. Improved Plough for underdraining Land, 288 328 ib. 17. Improvements in the Art of making Paper in separate Sheets, 336 18. Analytical Researches on certain Bodies, Crank useful in working Telegraphs, and Improvement in Jury Masts, 352 Specification of the Patent granted to RICHARD TREVI THICK, of Rotherhithe, in the County of Surrey, Engineer, and ROBERT DICKINSON, of Great Queen-street, in the County of Middlesex, Esquire; for certain Ma chinery for towing, driving or forcing, and discharging Ships and other Vessels of their Cargoes, and applicable to other useful Purposes. Dated July 5, 1808. To all to whom these presents shall come, &c, NOW KNOW YE, that in compliance with the said proviso, we the said Richard Trevithick and Robert Dickinson do hereby declare, that our said invention is described in manner following; that is to say: In a ship or vessel properly constructed for the purpose, and to which we give the name of a nautical labourer, we place a rowing wheel, shaped like an undershot water-wheel, furnished with floats or pallets, but which we call our propelling boards, and of a size proportioned to the vessel; the said rowin gw heel is placed vertically in a box or casing VOL. XV.-SECOND SERIES, fitted B fitted to receive it, in such a manner that its axis shall be at right angles to the length way of the ship or vessel, while the edge of the propelling board that is the lowest, shall be even with the keel of the ship or vessel, or ra ther with the keels, for we prefer having two, and placed at such a distance from each other as just to allow the propelling boards of the rowing wheel to pass freely between them. The aforesaid box or casing which contains the rowing wheel, is made air-tight, and is open only at the bottom, where the floats are intended to act in propelling the vessel, and the water is prevented from rising in the said box or casing by an air pump, forcing air into it so as to keep the water always down at the level intended. The end or ends of the axle of the rowing wheel works or work in a collar or collars of leather, or any other substance fitted to prevent air from passing out, And the said wheel, as also the fore-mentioned air pump, is worked by means of a crank, a wheel, or any other suitable contrivance, at one or both ends of the axle, and connected with a steam engine, which is the power we employ to move the rowing wheel, or, in other words, to give the required movement to the vessel; in the wheel itself there is no novelty, the novelty of this part of our invention consists in working the wheel in an air vessel, and by means of the contained air, keeping the surface of the water at such a lower level than the general surrounding surface, as may prevent the water from flooding the wheel. When we mean to employ such a vesseļ or ship and apparatus as the above, for the purpose of towing other vessels, the propelling boards of the rowing wheel, and also the steam engine, must be larger in proportion to the work intended to be performed; the vessels |