Measurements, Electrical

— Measurements of the various effects exhibited in electrical phenomena, especially practical measurements in connection with the electric circuit. Every system of measurement is based upon some experimental fact or law. An electric current can: 1, cause a deposition of metals from their chemical solutions; 2, heat the wire that it flows through; 3, attract (or repel) a parallel neighboring current; 4, accumulate as an electric charge that can repel (or attract) a neighboring charge of electricity; 5, produce in its neighborhood a magnetic field, that is to say, can exert a force upon the pole of a magnet placed near it, as for example, in galvanometers. his last is made the basis in the system now adopted by international agreement; and it is the best because, firstly, it connects the electrical units with the magnetic ones, and secondly, it is closely connected with the mechanical units, enabling the mechanical values of the electrical quantities to be readily computed Instruments for measuring currents of electricity are of many styles. As a mysterious and invisible element is dealt with, the measurement is indirect. The effects of currents of various pre ures and volumes are what are measured, not the currents themselves.