A Dust Electricity Analyzer

Abstract

An apparatus is described by means of which the size and the charge of large numbers of microscopic particles can be simultaneously determined. The method is based on Hopper and Laby's work on the determination of the electronic charge, i.e., horizontal deflection of particles settling under gravity recorded photographically. The procedures involved are given in some detail, and the nature and limitations of the general results are discussed. Simplicity of operation and design are emphasized to render the instrument a workable tool in industrial research.