Pendulum Apparatus Sterneck

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Item Pendulum Apparatus Sterneck
Item code
Description Explanation of use
Manufacturer Askania
Location Houston Geoscience Center
Serial number
Taxonomy Pendulum

von Sterneck Pendulum Apparatus. 1900, Stuckrath, Berlin This apparatus is a modified version of that developed by von Sterneck in 1882 for the purpose of investigating the variation of gravity encountered in deep mines. The instrument shown here with its air tight outer casing removed comprises three 25cm pendulums together with a dummy pendulum carrying a thermometer. With the casing in position, the pendulums could be started and stopped from outside and the thermometer and mirrors observed through the windows. The box alongside contains flash apparatus for the purpose of observing coincidences between a chronometer and the pendulum. An electromagnet in circuit with the chronometer moves a shutter at the end of each second throwing a flash of light through a site onto the pendulum mirror. The apparent position of the reflected flash depends on the position of the pendulum at the instant of reflection. The period of swing being slightly more than half second, the pendulum tags behind the chronometer. The set of apparatus shown here together with its chronometer and along with the British Antarctic Expedition of 1901 and on the Egyptian Survey of 1909-1913 and by Gravitational sites in 1920.