William Lax

William Lax
Cover of Remarks on a Supposed Error in the Elements of Euclid
Born	1761 Ravensworth, North Riding of Yorkshire, England
Died	29 October 1836 St Ippolyts, Hertfordshire
Citizenship	British
Nationality	English
Fields	Astronomy, mathematics
Institutions	University of Cambridge Board of Longitude Fellow of the Royal Society
Alma mater	Trinity College, Cambridge
Known for	Remarks on a Supposed Error in the Elements of Euclid Tables to be Used with the Nautical Almanac
Notable awards	Smith's Prize
Notes
His daughter Margaret married Andrew Amos.

William Lax FRS (1761 – 29 October 1836) was an English astronomer and mathematician who served as Lowndean Professor of Astronomy and Geometry at the University of Cambridge for 41 years.

Lax was born in Ravensworth in the North Riding of Yorkshire. He attended Trinity College, Cambridge and graduated Bachelor of Arts as the Senior Wrangler and first Smith's Prizeman of his year. He was elected a fellow of Trinity College, ordained as a minister, and received his Master of Arts. Lax was granted the livings of vicar of Marsworth, Buckinghamshire and of St Ippolyts near Hitchin, Hertfordshire, where he erected an observatory.

Lax was best known for his Remarks on a Supposed Error in the Elements of Euclid (1807) and his work regarding the Nautical Almanac, which was an important reference for navigation in the period. An obituary claimed that "To whatever Professor Lax applied, he made himself completely master of it". His daughter married Andrew Amos and through that line Lax is the grandfather of Sheldon Amos and the great grandfather of Maurice Amos, a notable legal dynasty.

Lax was born in the village of Ravensworth, near Richmond in the North Riding of Yorkshire, England, the son of William (1731 – 19 August 1812) also born in Ravensworth, and Hannah Lax (1738 – 10 June 1811). He was christened on 27 October 1761 in Burneston. He was educated at the Kirby Ravensworth Free Grammar School, where he learned Latin (in which he became fluent) and Greek as well as English language, arithmetic and mathematics. Although the school was subsidised by a charitable trust, "Free" in the context of the school's name meant free from all authority save for the Crown.