Einrichtung zum Messen von Abweichungen von der Vertikalen

1, 244, 533. Measuring angular displacement electrically. DATAWELL N.V. Aug. 25, 1969 [Aug. 27, 1968], No.42171/69. Heading G1N. Apparatus for measuring angular displacements from the vertical comprises a liquid-filled vessel 1 having a spherical internal surface from which a rigid bar 10 projects radially to the centre of the sphere to support a winding 5 by means of a thread 3 so that winding 5 is always horizontal, two further mutually perpendicular windings 8, 9 being mounted on the vessel concentrically therewith. In use, current is supplied to the winding 5 through one or more conductors inside the suspension thread 3 so that departure of either of windings 8, 9 from the vertical causes a voltage to be induced in it which voltage is proportional to sin Á where Á is the angular displacement from the vertical. In an alternative embodiment Fig. 46 (not shown) the liquid filling the vessel is electrically conducting and forms the return path for alternating current to the winding 5. The vessel may be carried by a ship or buoy. It is stated that if the azimuth orientations of the windings 8, 9 are known then the geographic orientation of the inclination of the windings may be determined and hence the direction of propagation of ocean waves, where the vessel is on a buoy.