We have traced the smooth-bore cannon through the successive stages of its evolution. It is now proposed to give, in the form of a biographical sketch, an account of the inception of scientific methods as applied to its use, and at the same time to pay some tribute to the memory of the man who laid the foundations deep and true of the science of modern gunnery. One man was destined to develop, almost unaided, the principles of gunnery as they are known to-day. This man was a young Quaker of the eighteenth century, Benjamin Robins. For a variety of reasons his fame and services seem never to have been sufficiently recognized or acknowledged by his own countrymen. To many his name is altogether unknown. To some it is associated solely with the discovery of the ballistic pendulum: the ingenious instrument by which, until the advent of electrical apparatus, the velocities of bullets and cannon balls could be measured with a high degree of accuracy. But the ballistic pendulum was, as we shall see, only one manifestation of his great originating power. The following notes will show to what a high place Robins attained among contemporary thinkers; and demonstrate the extent to which, by happy combination of pure reason and experiment, he influenced the development of artillery and fire-arms. His _New Principles of Gunnery_ constituted a great discovery, simple and surprisingly complete. In this work he had not merely to extend or improve upon the inventive work of others; his first task was to expose age-long absurdities and demolish all existing theories; and only then could he replace them by true principles founded on correct mathematical reasoning and confirmed by unwearying experiment with a borrowed cannon or a “good Tower musquet.”