During a period of several years, dating from about 1851, Wm. Mount Storm, an inventor and engineer of considerable note, made a series of experiments with air and gases in connection with steam, with a view to promote economy in fuel used for generating motive power. An engine, called the » Cloud Engine,» was exhibited by him at the Fair of the American Institute in 1855. The engine was named as above from the fact that the air, which was mingled in the cylinder with the steam, changed the latter into a vesicular condition, resembling fog. The inventor claimed 33 per cent, and those who saw it state that, at times, it did actually make a gain of even more than this. Its operation was, however, fitful and unreliable, and it finally was withdrawn from public attention, and nothing more has been heard from it. None of these experiments, however, seems to have been made on the same principles as those of Mr. GeC>i»,e Warsop, of Nottingham, whose object is to attain to a method whereby the expansive force of heated air may be used in an engine without the difficulties attending the use of heated air alone in the cylinder, and which are met with in the engines of Ericsson, and others employing only heated airs. In Warsops experiments the object seems to have been to make steam assist in applying the expansive force of air. Warsop, however, has found that a maximum effect from mixed air and steam depends upon the proper proportion of the two gaseous bodies, a conclusion which might have been theoretically drawnrom a consideration» of the relative capacities of air and steam for heat. Still such an inference would scarcely have warranted great hopes of economy from this source without extended experiment, and although extraordinary resultsstated in a former articleare claimed, we shall not be surprised to hear that some offset to these claims has ere long been discovered. Incidental to the results sought by Warsop is of course a better circulation in the boiler employed to generate the steam used in the experiments, from which some gain might be expected, though nothing like what is claimed. In December; 1866, D. B. Tanger, of Bellefontaine, Ohio, took out a patent for a steam generator, between which and the apparatus of Warsop we can recognize no essential dif ference. Joseph Whitworth, the inventor of the Whitworth gun, and Wm. Fairbairn, the celebrated engineer, have been created baronets. 1869 SCIENTIFIC AMERICAN, INC. October 9, 1869.] 233 MUNN &. COMPANY, Editors and Proprietors. PUBLISHED WEEKLY AT NO. 37 PARK ROW (PARK BUILDING), NEW YORK O. D. MUNN, S. H. WALES, A. E. BEACH. Blir » The American News Company,» Agents.121 N assaa street.New York. The New York News Company,» 8 Spruce street. Messrs. Sampson, Low, Son & Marston, Crown Building, 188 Fleet st.; Tubner & Co.. 60Paternoster Row. and Gordon & Gotch, 121 Holborn Hill, London, are the Agents to receive European subscriptions. Orders sent to them will be promptly attended to. tW A. Asher & Co., 20 Unter den Linden, Berlin, are Agents for the German States. VOL. XXI., No, 15 ... [New Series.]. .. TweMty-/our<7i Year. NEW YORK. SATURDAY, OCTOBER 9, 1869. Contents: (Illustrated articles are marked with an asterisk.) *The Glass Wor»ks of the Depart. ments of the Loire and Rhone, France...........................225 What English Workmen Think of Free Trade.......................226 Dust..................................2 26 What is Found ill the Air...........227 l Value of Meteorological Observa tions..............................227 Establishment of Soap Factories..227 Watering Streets with Saline Solu IF. tions..............................227 A Small Engine......................227 *Improved Siding Hook and Com bined Tool......................228 Stewart and 1aits Experiments oil the Heating of Bodies by Rotation, in Vacuo....................228 Waterproofing Walls.................228 ...•229 Dried Grass........229 Coating Castings with Gold and SilVer......f.....................223 Preparation of Sizes for Guilding.2Z9 *Death-WatchNatural Size and Magnified........................220 Utilization of Pine Leaves.........229 Invention of the Spin Level......229 The Colorado Expedition......229 The Assimilation of Inorganic Substances in the Animal Economy................................230 Spectrum Lines of Aurora.........230 Cutters on Reaping Machines......230 The Scientific American under a Comer Stone...................230 The Hartford Steam Boiler Inspection and Insurance Company .. .-...........................230 ObituaryThomas Graham, Chemist.................................230 Gas for Lighthouses.................230 Darwinism and Design..............231 How to Preserve Pencil Drawings.231 Extraordinary Phenomenon........231 Radiation of Heat from the Moon.231 Persine...............................231 Editorial Summary..................2ol *lmproved Machine for Cutting Staves............................232 •Sibleys Improved Leveling Instrument .........................-232 The Phosphoroscope................232 Aero-Steam EnginesStorms Experiments........................232 Steam Pipes as Causes of Fire......233 American Engineering in China....233 The Exhibition of the American Institute ...........................233 (Important Patent Decision.........235 Manufacturing, Mining, and Railroad Items----.T.................235 New Publications....................235 Inventions Patented in England by Americans....................-36 Answers to Correspondents........236 Kecent American and Foreign Patents.............................236 List of Patents.......................237