On Sa/ine Crystallization. By Andrew Ure, M. D. Professor of the Glasgow Institution, 07id Member of the Geological Society.From the Journal of Science and the Arts, Edited at the Royal Institution*It is well known that water and solutions of some salts will, under certain circumstances, preserve their fluidity, though cooled down many degrees below their ordinary congealing or crystallizing temperature. The most convenient, and perhaps striking mode of exhibiting this phenomenon, is to fill a phial with a hot saturated solution of sulphate of soda, to cork it well, and set it to cord in a quiet place. When the cork is afterwards withdrawn, the liquid stratum at the sujface instantly becomes a solid, with a peaily lustre; then ‘lie parts beneath