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Star (Christchurch), Issue 687, 5 August 1870, Page 2

The schooner Shepherdess, Captain Sedcole, which arrived in harbour on Friday evening from the Bay of Plenty, reports that when off Flat Point she passed a portion of a vessel's deckhouse, floating bottom part up. It had two broken beams and a broken iron knee, and did not seem to have been long in the water. —Wellington Evening Post, July 27. Recently a number of scientific gentlemen and others opposed to the railroad monopoly met at TrentOD, New Jersey, for the purpose of witnessing an experiment of a model steam propeller. The inventor is Mr William F. Goodwin, Metuchen, New Jersey. The most novel feature of the new propeller consists in having the propelling wheel placed at the bow end of the boat instead of at the stern. The boat is constructed in the form of a scow, with the sides straight and parallel . and projecting in advance of the body of the boat sufficiently to enclose the propelling wheel, made to float upon the surface of the water moving or vibrating round the driving shaft. It has been considered a well settled principle in navigation that the amount of water which a boat will displace is just the same, whatever may be her form, and that the motive power required to force a boat through the water can be diminished only by , . the employment of acute angles or sharp lines in the construction of her bow and stern. But this involves considerable expense, and diminishes the amount of storage room, besides lessening considerably the buoyancy of the boat. In like manner there is a vacancy created at the stern, which must be filled by the replacement of the water before the boat can procaed. It follows that the power required to effect this displacement and replacement of water must exist in addition to the power absorbed in overcoming the inertia of the boat itself and the friction ' of the water upon her bottom and sides. :. It is known by actual experiment that ninetenths of the power used in ordinary steam- *■• boats are required to displace the water, while only one-tenth ia sufficient to propel! the boat after the water has been displaced. The preceding difficulties are all overcome in the new propeller. The projecting sides serve the double purpose of receiving the entire body of water to be displaced and confining it while acted upon and forced down by the wheel, conducting the water under the boat and at the same time preventing the commotion of water made by the wheel from communicating with the water on the out- * side.