It is mainly a torsion balance combined with a Leyden-jar.
"A Treatise on Meteorological Instruments" by Henry Negretti
The torsion balance was enclosed in a case and outside this two lead spheres WW each 12 in.
"Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 4" by Various
This was found to upset the balance, the resultant torsion being anti-clockwise.
"Life Movements in Plants, Volume II, 1919" by Sir Jagadis Chunder Bose
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Merkowitz, Measurement of newton’s constant using a torsion balance with angular acceleration feedback, Phys.
New Regions for a Chameleon to Hide
The microgravity conditions also allow for an improved design of the null experiment, free from the geometric constraints of the torsion balance.
Experimental Tests of General Relativity
Torsion Balance Investigation of the Finite Temperature Casimir Force.
Precision studies of Casimir force and short-range gravity employing prototypes of interferometric gravitational wave detectors
Observation of Finite Temperature Casimir Effect in a Torsion Balance Experiment.
Precision studies of Casimir force and short-range gravity employing prototypes of interferometric gravitational wave detectors
To date, the highest precision, of order 10−12 , has been achieved by torsion balance experiments, but the STEP experiment is designed to reach a precision of 10−18 .
Principles of Equivalence: Their Role in Gravitation Physics and Experiments that Test Them
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