|Place of work||Greenwich|
||30 Jul 1781 – 29 Sep 1786
|Born||1756, Nov 3
Born in Heath (a small village near Wakefield, Yorkshire), Joseph Lindley took over as Maskelyne’s assistant from George Gilpin in 1781 and was succeeded by Thomas Horrox in 1786.
Having shown an early talent for mathematics, Lindley had travelled to London with a letter of reference to the firm Prescott, Grote and Co., bankers where he started work as an apprentice clerk. It is said that Prescott oversaw his training himself, and recognising Lindley’s talent recommended him to Maskelyne as an assistant.
As well as his regular duties at the Observatory, Lindley was also involved in the testing of Mudge’s timekeepers (Blue and Green) for the Board of Longitude for which he received additional payment. (Click here to view the manuscript documents relating to these payments).
Although the difference in longitude between the Greenwich and Paris Observatories had been determined a number of times in the past, there was still a great deal of uncertainty as to its true value. To this end, William Roy began a trigonometrical determination in 1784, which was eventually completed in 1790. In the meantime, in 1785, Maskelyne organised for it to be determined by Lindley who was required to transport a number of chronometers to Paris in order to determine the time differene and hence the longitude difference from Greenwich. (RGO4/327)
Following his resignation, Lindley embarked on a county survey of Surrey with William Crosley for which Roy cooperated by allowing access to his as yet unpublished data. This enabled the map, which was published in 1793, to be rooted to an accurate distance scale. It was the forerunner of the first Ordnance Survey maps.
In addition to his earlier work for the Board of Longitude, Lindley was also involved in testing Wain’s Horizon for the Board for which he received payment in 1795.
Lindley was twice married. His second wife was the daughter of Michael Searles architect of the Paragon in Blackheath (now grade 1 listed). His image is preserved in a pastel-portrait by the leading artist John Russell who also made a chalk study of Maskelyne in about 1776. His son William was a famous engineer as was his grandson Sir William Lindley. His great grandson William Maximilian Lindley (1891–1972) was Director of the British Astronomical Association’s variable star section.
Memoir of a map of the county of Surrey; from a survey made in the years 1789 and 1790. By Joseph Lindley, late assistant to the Astronomer Royal at Greenwich, and William Crosley, land surveyor. J. Lindley, London, 1793