Time measuring instruments
Found in 5 Collections and/or Records:
'An Account of the going of Dr Maskelyne's new Chronometer N.309 made by Mr T. Earnshaw', 1799 - 1811
Also contains results for 'A continuation of the trial of the late Dr. Postlethwaite's watch' from 12 August - 30 September 1799.
Astronomical observations made at the Island of Barbados, 1763 - 1764
Letter from Nevil Maskelyne, 1765
The draft letter is addressed to 'My Lord' and is a response to John Harrison's applications to the Board of Longitude and to Parliament to get a second £10,000 in reward money for his marine timekeepers. The letter continues with notes on longitude determination and marine timekeepers by other makers.
Notes taken at the discovery of Mr Harrison's time-keeper, 1765
Observations on the workings of John Harrison's time-keeper, in two parts.
Trials of Harrison's chronometers, 1766 - 1771
Observations and comparisons during the trials of John Harrison's chronometers (H1, H2, H3 and H4) and Kendall I, with mean solar time, 1766-1767, and the rating of the Royal Observatory transit clock, 1771. The volume is comprised largely of tables of measurements, with some descriptions of how the results were achieved.