The author has attempted to supply a great desideratum in the practice of marine engineering, by instituting a series of experiments to ascertain what force the waves exert against opposing barriers.

For this purpose he suggests, in some peculiar situations, the use of columns of water or of air, by which the force of each wave can be ascertained; in the one case by the rise of the water-column, or in the other by a pressure-gauge, shewing the same result in atmospheres by compression.