EPISTLE

original: "Ingenieux" to his late Highness (of perpetual memory) and having died in your service, traced many foundations of your city—as admirable as it is beautiful—through his Geometry The mathematical study of spatial properties, essential for 17th-century fortification and profound dexterity. Thus, we have jointly gathered from various Authors what seemed to us to be appropriate for our design, and have added what our own invention dictated to us; in order to create six small books, divided into: how to properly attack one's enemy with machines; how to properly defend oneself with the same; writing on things common to both; making artificial fires original: "feux artificiels"; incendiary weapons or early explosives used in combat for war; pleasure fires original: "feux de plaisir"; decorative fireworks for celebrations; and the final part concerns the Alphabet likely referring to a system of signals or a cryptographic code, about which I have sometimes had the honor of conferring with your Highness. Now, insofar as highly courageous and arduous things can only be put into execution by magnanimous hearts—and since attacking is the most noble part of military actions—it seemed fitting to us to ad-