Abstract
(1) The equation of motion of the needle of Benndorf's self-recording electrometer was solved when the potential of the needle was kept constant, the potential of the “Referenzpunkt” kept constant and the latter varied periodically.
(2) Constants ω and κ were determined from the observation of the motion of “Zeiger.” The relation of κ and the density of sulphuric acid, derived from the increase of its volume, is illustrated in Fig. 1. The value of κ also varies according to the position of the mica-vane in the liquid. It is noticeable that κ becomes larger when the upper rim of the mica-vane approaches the liquid surface.
(3) A method of determining the leaking-rate of the whole electric system under the working state of the collector was proposed. Which involves the observation of the motion of “Zeiger” when the potential of the needle increases from zero by the action of the collector.
(4) The position of the “Zeiger” after one or two minutes in the damped oscillation which was initially caused by the kick of the lever-work was calculated with the observed κ and ω.
(5) The decrease of amplitude and the phase retardation of the oscillation of the needle, when the potential of the “Referenzpunkt” varied periodically, was calculated with observed κ, ω and α+β for some given periods.
