Written by Leonhard Zubler, a Swiss goldsmith and instrument maker who is credited with popularizing the use of the plane table as a tool for surveying, Novum instrumentum geometricum illuminates the shared history of land-surveying and militaristic range-finding technologies. The text is intercut with elaborate copperplate engravings that showcase the might of trigonometry and triangulation in the immediacy of conflict. Bombardiers pack canons that are aimed with advanced precision at distant towers; the construction of ornate fortifications are planned with ease thanks to geometric instruments; and seemingly insurmountable crags are brought down to earth through the surveyor’s sightline. Readers are promised that they will learn how to measure the width of a moat or the height of wall in order to breach them more efficiently.

Novum instrumentum geometricum mainly features images related to an early modern instrument known as the triquetrum or Dreistab, a three-armed ruler, with two pivot points, used for charting angles in the heavens and on earth. Zubler most often showcases a two-armed variation known as the Zweistab, which includes a “finely divided scale and micrometer slide for exact settings”, writes Uta Lindgren. As if to show the versatility of this technology, the instrument is wielded on the masts of ships, balconies, and by a man perched atop the stump of a felled tree — even comically enlarged to depict its arms stretching out to touch the objects of their reconnaissance. Frequently two instruments are employed in parallel, by a pair of figures a fixed distance apart, which would allow the surveyors to estimate the distance to a far away point using trigonometry.

Little is known about Leonhard Zubler (b. 1565), aside from his divorce in 1604, and probable death by plague circa 1611. He once created an extensive plan for modernizing the cityscape of Zurich, which was subsequently lost. During his lifetime, Zubler’s instruments were so desired that he was able to open a commercial outlet in Frankfurt am Main in 1608.