The cloud chamber as a tool in cloud physics

Abstract

Since 1875 when Coulier and, a little later, Aitken made the first simple expansion cloud chambers to study the condensation of water vapour on atmospheric particles, and particularly since 1895 when C. T. R. Wilson made his famous instrument with the initial object of studying optical phenomena in clouds, the cloud chamber has been one of the principal tools for investigating condensation phenomena and for simulating natural cloud-forming processes. The cloud physicist commonly employs expansion-, mixing- and diffusion-cloud chambers (he has yet to find a use for the bubble chamber) for studying the spontaneous condensation of water vapour; condensation upon ions and atmospheric particles; the production, nucleation and crystallization of super-cooled clouds; the properties of ice-forming nuclei; and the growth of ice crystals from the vapour. The purpose of this article is to review some of the more important aspects of this work.