Improvements in or relating to the determination of relative plummet deviations for prospecting for minerals and other subterrestrial deposits

摘要

493,738. Measuring gravitational forces. BOLIDENS GRUVAKTIEBOLAG. Jan. 31, 1938, No. 2954. Convention date, March 19, 1937. Drawings to Specification. [Class 97 (iii)] In measuring the variations in the horizontal component of the force of gravity from relative plummet deviations, the image of a fixed object, e.g. a scale or point source of light, is reflected into a fixed telescope by a mirror or prism attached to the suspension cord of the plummet. The plummet is moved to a number of different stations whilst the telescope and scale remain fixed. The plummet and mirror may be housed in a temperature regulated casing provided with a window. Alternatively, the telescope, scale, plummet, and mirror may all be encased in a large evacuated and temperature regulated tube.