Gemma Frisius

Gemma Frisius (/ˈfrɪziəs/; born Jemme Reinerszoon;[1] December 9, 1508 – May 25, 1555) was a Dutch physician, mathematician, cartographer, philosopher, and instrument maker.

Frisius was born in Dokkum, Friesland (present-day Netherlands), of poor parents who died when he was young.

One of his most influential teachers at Leuven was Franciscus Monachus who, circa 1527, had constructed a famous globe in collaboration with the Leuven goldsmith Gaspar van der Heyden[2] Under the guidance of Monachus and the technical assistance of Van der Heyden, Frisius set up a workshop to produce globes and mathematical instruments which were praised for their quality and accuracy by contemporary astronomers such as Tycho Brahe.

His students included Gerardus Mercator (who became his collaborator), Johannes Stadius, John Dee, Andreas Vesalius and Rembert Dodoens.

According to an account by his son, Cornelius, Gemma died from kidney stones, which he had suffered from for a minimum of 7 years.

Gemma Frisius , ( Maarten van Heemskerck , c. 1540–1545)
Gemma Frisius's famous 1536 terrestrial globe
Gemma Frisius's 1533 diagram introducing triangulation into the science of surveying