Recent acquisition: Johann Tobias Mayer, Tabulae motuum solis et lunae novae et correctae … Quibus accedit methodus longitudinum promota … editae jussu praefectorum rei longitudinariae. Edited by Nevil Maskelyne. London, William and John Richardson, 1770. 4to, pp. [viii], 89, [6], 92-136; CXXX, [2]; a fine copy in contemporary calf. First edition.

In her best-selling book, Longitude, Dava Sobel recounts how an Act of the British Parliament in 1714 established a Longitude Prize of up to £20,000 to be awarded to anyone who could discover a method of determining longitude at sea. Like many other prize-seekers, J.T. Mayer believed the answer would lie in the stars, so that a more accurate calculation of lunar and solar positions would enable sailors to fix their location at sea.

Mayer’s lunar and solar tables attained an accuracy of ± 1’, so in 1755 he submitted them to the Admiralty in hopes of winning the prize. Although Mayer failed in that attempt, after his death in 1762, Mayer’s widow resubmitted them to the Board of Longitude, which awarded her a prize of £3,000.

Sobel explains that the solution to the longitude problem came from a different angle: the craftsman John Harrison invented a clock of impeccable accuracy which, since it did not rely upon a pendulum, could survive the worst conditions at sea.

Mayer’s posthumously published tables were used to compute the lunar and solar positions in the early editions of The Nautical Almanac of Greenwich Observatory.

The OU copy of Mayer (1770) belonged to the Earls of Macclesfield, Shirburn Castle, as indicated by an engraved bookplate, a shelfmark on the front pastedown, and a blindstamped Macclesfield crest in the blank margins of the first three leaves.

View Mayer (1770) gallery.