Adriaan van Roomen

Adriaan van Roomen (1561 to 1615), also known as Adrianus Romanus, was a mathematician, professor of medicine and medical astrologer from the Duchy of Brabant in the Habsburg Netherlands. He worked in algebra, trigonometry and geometry and became famous for computing pi to sixteen decimals, surpassing the ten digits that François Viète had reached. His work on the circle, In Archimedis circuli dimensionem expositio et analysis, appeared at Würzburg in 1597. He also solved the Problem of Apollonius with intersecting hyperbolas and wrote on the Gregorian calendar reform. He taught at Louvain and Würzburg, served as mathematician of the king of Poland and as physician to the court of Rudolf II. In this atlas he is an early record holder in the hand calculation of pi.