On phenomena occurring in the condensation of molecular streams on surfaces

Abstract

R. W. Wood first investigated the phenomena occurring when a stream of metallic vapour is allowed to impinge on a surface of glass or other material, the vessel in which the experiment takes place being evacuated. Under these conditions the rate of condensation depends very largely on the temperature of the surface. Wood showed that for temperatures below —140°C. the probability of a mercury atom adhering to the surface, after one impact, was unity; no atoms were reflected; whilst for higher temperatures only a proportion of the atoms could be considered to adhere after the first impact. Similar phenomena were observed for other metals.