Born Ramsey, Huntingdonshire, England, 1711
Died Cambridge, England, 10 March 1775
Richard Dunthorne was an observer, mathematical astronomer, and surveyor. Dunthorne’s father was a gardener who sent his son to the free grammar school at Ramsey. Here he was noticed by Roger Long, master of Pembroke Hall, Cambridge, who employed Richard as a footboy in return for a mathematical education.
Dunthorne taught at a Cambridge University preparatory school in Coggeshall, Essex, before returning to Cambridge in the 1750s as butler and astronomical observer to Pembroke Hall. He held the post for the rest of his life. He was also scientific assistant to Long until Long’s death in 1770. In addition, Dunthorne was superintendent of the Bedford Level Corporation, for which he conducted a survey of the fens and was responsible for lock building and drainage work. From 1765 to his death, Dunthorne was a comparer for the Nautical Almanac.
Despite never formally graduating from Cambridge University or holding an academic post, Dunthorne made several contributions to mathematical astronomy. In 1739 he published The Practical Astronomy of the Moon, or New Tables of the Moon’s Motion. The tables were based on Isaac Newton ’s lunar theory, and Dunthorne went on to use the tables to compare lunar longitudes computed from his tables with longitudes obtained by observation. He published the results in the Philosophical Transactions of the Royal Societyin 1747. When Tobias Mayer was awarded £3,000 in 1765 for his work on the motion of the Moon, Dunthorne wrote to the Board of Longitude pointing out that he had published similar ideas some years before, but the board declined to reward him.
Dunthorne continued to study the Moon, publishing a letter in 1749 giving a figure for the acceleration of the Moon’s mean motion that he had calculated using eclipse data going back 2,000 years. He also made contributions concerning comets and developed plans for new tables of the motions of Jupiter’s satellites.
In 1765, Nevil Maskelyne appointed Dunthorne as the first comparer of the Nautical Almanac. Dunthorne was responsible for checking the work of the computers calculating the ephemerides and for selecting stars for the computation of lunar distances. In the same year, Dunthorne planned and funded the building of an observatory on the Shrewsbury Gate of Saint John’s College, Cambridge; he also donated the instruments necessary to fully equip the observatory. From here Dunthorne observed the 1761 and 1769 transits of Venus.
- Clerke, Agnes M. and rev. by Anita McConnell (2004). “Dunthorne, Richard.” In Oxford Dictionary of National Biography, edited by H. C. G. Matthew and Brian Harrison. Vol. 17, pp. 365–366. Oxford: Oxford University Press.Google Scholar