A Steamer Propelled By A Fan

-Weearn from the English papers that a boat constructod on the principie of a 'fan' ropeller has been launched at Greenwich, and a very successful experimental rip performed in her. The boat is named the Mystery - ia of about fifty tons burheu, and twenty horse power. The enengines are fixed lengthways in the vessel. The propeller is constructed simiarly to the fan of a windmill, and like the screw, is fixed to the stern. It possesses a two-fold action - one perpetrdicu-' ar, which regulates her speed, and the other horizontal, which describes half a circle, and regulates her steerage. This latter action of the 'fan' is of such power, that while it supersedes the use of a rudder, it can wheel the boat round as if she moved upon a pivot, and continue to spin her round like a top, without making iicad or stern way, except what little the tide or wind may effect. This peculiar action of the 'fan' can be attached to any 6ailing vessel, from a line-of-battle-ship down ío a collier, and can be worked by hands, totally unconnected with steam. - - lts power, though not sa great as when worked by steam, is such that it woulc enable a ship-of-the-line to bring both her broadsides ío bear ngainst nn enemy in