Abstract
In the years 1878 and 1879 the American physicist Alfred Marshall Mayer published his experiments with floating magnets as a didactic illustration of molecular actions and forms. A number of physicists made use of this analogy of molecular structure. For William Thomson they were a mechanical illustration of the kinetic equilibrium of groups of columnar vortices revolving in circles round their common centre of gravity . A number of modifications of Mayer's experiments were described, which gave configurations which were more or less analogous to Mayer's arrangements. It was Joseph John Thomson who, in publications between 1897 and 1907, used Mayer's results to obtain a good deal of insight into the general laws which govern the configuration of the electrons in his atomic model. This article is mainly concerned with Mayer's experiments with floating magnets and their use by a number of physicists. Through his experiments Mayer made a significant, although small, contribution to the theory of atomic structure