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Page:Aerial Flight - Volume 1 - Aerodynamics - Frederick Lanchester - 1906.djvu/363

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EXPERIMENTAL AERODYNAMICS.
§ 226

when in rapid motion is overcome electrically, the range of motion permitted to the lever being limited by stops to about one degree, the stops forming at the same time electrical connections to alternative circuits.
Fig. 142.
The two circuits are arranged in connection with a galvanometer so that contact with one stop causes a current in one direction and contact with the other causes a current in the opposite direction. When equilibrium is established the galvanometer needle either remains unaffected, or oscillates from one side to the other indicating that the current flows about equally in either direction.

§ 226. Dines' Results. Direct Resistance.—A considerable number of experiments on the resistances of planes and solids of various forms are found summarised in the following table, which is taken intact from the “Experiments on the Pressure and

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