device used to measure the gravitational acceleration at the Earth`s surface. Other such devices, using different methods to obtain the same result, ... [3 related articles] Found on http://www.britannica.com/eb/a-z/t/64
A torsion balance is an instrument which was invented by Coulomb for measuring electric and magnetic attraction. A fine silver wire supports, at its centre of gravity, a horizontal carrier with bodies of known electric charge at each end, or a magnet of known strength. The deflection of the carrier determines the strength of the attractive force wh... Found on http://www.probertencyclopaedia.com/browse/GT.HTM