ENCOUNTERS BETWEEN ROBINS, AND EULER AND THE BERNOULLIS - ARTILLERY AND RELATED SUBJECTS

Euler (1707-1783) was a close friend of the Bernoulli family, and John Bernoulli I as a result of not winning a French Academy prize offered for essays on the subject of Impact, published his effort-only to have it examined and worsted by criticism from a then young, unknown 20 year old, Benjamin Robins (1707-1751). This encounter probably led Robins to his work in ballistics, the ballistic pendulum for measuring musket ball speed and the writing of his New Principles of Gunnery, ultimately published in 1742. Euler (born in the same year as Robins), and presumably knowing of the latter scientific clash, seemingly became interested in artillery and the trajectories of projectiles. His first work is dated 1727, three months after Robins' critique of Bernoulli, but it was not published until many years afterwards. Also, through association with the St Petersburg Academy, by means of which Peter the Great intended to build up the Russian Navy and commerce, Euler likely developed his deep interest in naval science, tides, fire, meteorology and artillery. Robins' book was devoured by Euler and in 1745 he brought out his own book, in German, on The New Principles of Artillery, which contained a translation of Robins' book with sections containing "Anmerkung" (Remarks) which brought it up to several times the length of Robins' own book. Fortunately, the latter was translated from German into English by Hugh Brown and appeared in 1777. Almost nothing has been written by latter-day authors concerning the interaction of Robins and Euler, and somewhat the Bernoullis, apart from that of Truesdell and Scherrer. The latter's editorial and prefatory work on Robins is in German, as is all of Euler's writing in German, French or Latin. Truesdell's writings of interest to us are in English but are mostly confined to matters of fluid dynamics. The immediate aim of this paper is to make some of the details of the aforesaid interaction between Robins, Euler and the Bernoullis better known and to try to improve understanding of it, also casting light on some of the scientific questions of the mid-18th century.