Jost Bürgi

Jost Bürgi (1552 to 1632) was a Swiss clockmaker, mathematician and writer, active mainly at the courts in Kassel and Prague. Born in Lichtensteig in Toggenburg, he was an autodidact who was nonetheless counted among the most gifted mechanical engineers of his generation, and his employer William IV of Hesse-Kassel called him a second Archimedes in a letter to Tycho Brahe. He became court astronomer at Kassel in 1591 and in 1604 entered the service of Emperor Rudolf II in Prague, where he befriended Johannes Kepler. He constructed a table of sines, the Canon Sinuum, and some authors consider him one of the inventors of logarithms. As a clockmaker and instrument maker he introduced the cross-beat escapement and the remontoire, which improved the accuracy of clocks, and he built innovative mechanical astronomical models.