Dale, THOMAS

1797-1870. English sacred poet. D'Alembert, JEAN LE ROND. See ALEMBERT, JEAN D'. D'Alembert's Principle. Employed for reducing the determination of the motions of material systems to the conditions of solution of statical problems. The earliest step toward its discovery is found in a memoir by James Bernoulli in the Acta Eruditorum, 1686. It is this: if the effective moving forces of the several particles of a system be applied to them in directions opposite to those in which they act, they will conjointly with the impre ed moving forces constitute a system of forces statically disposed. See ALEMBERT, JEAN D'.