Bartholomew Pitiscus (1561-1613) was a mathematician and the Court Chaplain for Frederick IV, elector of the Palatine. In 1595, Pitiscus published a comprehensive trigonometry text, Trigonometria: sive de solutione tractus brevis et perspicius. This was the first time the word “trigonometry” was used to describe the study of the properties of triangles. This image is the title page of Pitiscus’s revised edition of his Trigonometria from 1600. As before, it considers the properties of spherical and plane triangles, particularly in the applied areas of geodesy, altimetry, geography, gnomonetry, and astronomy.
Pages 90 and 91 of Pitiscus’s Trigonometria discuss an illustrative example.