1 See Lord Kelvin, " Report on Electrometers and Electrostatic Measurements," Brit.
Electroscopes and electrometers, therefore, standing in proximity to electrified bodies can be perfectly shielded from influence by enclosing them in cylinders of metal gauze.
There are methods of measuring electrical power by means of electrostatic voltmeters, or of quadrant electrometers adapted for the purpose, which when so employed may be called electrostatic wattmeters.
9) used by him in connexion with his electrometers for maintaining their charge, closely resembles that of Belli's doubler and will be understood from fig.
His ampere-balances, voltmeters and electrometers, and double bridge, are elsewhere described in detail (see Amperemeter; Electrometer, and Wheatstone'S Bridge).
Lord Kelvin has classified electrometers into (I) Repulsion, (2) Attracted disk, and (3) Symmetrical electrometers (see VV.
The most important improvements in connexion with electrometers are due, however, to Lord Kelvin, who introduced the guard plate and used gravity or the torsion of a wire as a means for evaluating the electrical forces.
Symmetrical Electrometers include the dry pile electrometer and Kelvin's quadrant electrometer.
Quadrant electrometers have also been designed especially for measuring extremely small potential differences.