TRACT 34.

IN GUNNERY.

307

the method invented by the very ingenious Mr. Robins, anddescribed in his treatise on the New Principles of Gunnery,of which an account was printed in the Philosophical Trans-actions for the year 1743. Before the discoveries and in-ventions of that gentleman, very little progress had beenmade in the true theory of military projectiles. His bookhowever contained such important discoveries, that it wassoon translated into several of the languages on the con-tinent, and the late famous Mr. L. Euler honoured it witha very learned and extensive commentary, in his translationof it into the German language. That part of Mr. Robins’sbook has always been much admired, which relates to theexperimental method of ascertaining the actual velocities ofshot, and in imitation of which, but on a large scale, thoseexperiments were made which were described in my paper.Experiments in the manner of Mr. Robins were generallyrepeated by his commentators, and others, with universalsatisfaction ; the method being so just in theory, so simplein practice, and altogether so ingenious, that it immediatelygave the fullest conviction of its excellence, and the emi-nent abilities of the inventor. The use which our authormade of his invention, was to obtain the real velocities ofbullets experimentally, that he might compare them withthose which he had computed a priori from a new theory ofgunnery, which he had invented, in order to verify theprinciples on which it was founded. The success was fullyanswerable to his expectations, and left no doubt of thetruth of his theory, at least when applied to such piecesand bullets as he had used. These however were but small,being only musket balls of about an ounce weight: for, onaccount of the great size of the machinery necessary for.such experiments, Mr. Robins, and other ingenious gen-tlemen, have not ventured to extend their practice beyondbullets of that kind, but contented themselves with ardentlywishing for experiments to be made in a similar mannerwith balls of a larger size. By the experiments describedin my paper therefore I endeavoured, in some degree, tp