On the Vibrations of a Vortex Ring, and the Action upon each other of Two Vortices in a Perfect Fluid. Communicated by Lord Rayleigh. Received November 16, - Read December 8, 1881.

(London, Harrison and Sons, 1883). 4to. No wrappers as extracted from "Philosophical Transactions" 1883. Vol. 173 - Part II. Pp. 493-521, textillustrations. Fine and clean. First appearance of Thomson's second paper on the Vortex Atom. In 1882 he had won a prize with the subject "a general investigation of the action upon each other of two closed vortices in a perfect incompressible fluid"The first attempt to construct a physical model of an atom was made by Lord Kelvin in 1867. The main point was that in an ideal fluid, a vortex line is always composed of the same particles, it remains unbroken, so it is ring-like."In fact, the investigations of vortices, trying to match their properties with those of atoms, led to a much better understanding of the hydrodynamics of vortices - the constancy of the circulation around a vortex, for example, is known as Kelvin's law. In 1882 another Thomson, J. J., won a prize for an essay on vortex atoms, and how they might interact chemically. After that, though, interest began to wane - Kelvin himself began to doubt that his model really had much to do with atoms, and when the electron was discovered by J. J. in 1897, and was clearly a component of all atoms, different kinds of non-vortex atomic models evolved."(Michael Fowler).…