Letters to James Bradley and other correspondence.

1. Letter to Bradley on atmospheric pressure, with two examples of evidence provided by the author for his argument. There is also a piece on the origins of springs and rainfall by 'Academicus', an unknown pupil and admirer.

2. Equation written on a letter to Mrs Paine of Wanstead, Essex.

3. Letter to Mrs Woodom from Mathew Hymondefold, 11 October l729, informing her of the safe return home of him and his family. On the verso is a note concerning gravity.

4. Letter from Gael Morris, 29 October 1740, requesting information on the latitude of the Moon whilst in occultation with Jupiter. The letter encloses observations made by John Bevis and Mr Short.

5. Letter from Mathew Hymondefold to Bradley, 16 May 1741, regarding travel arrangements to Dorchester from Wanstead. On the verso is a chart of star positions for 21 December 1686.

6. Letter from Gael Morris, 1742, on finding the position of the Moon by observing two stars, with observations.

7. Letter from Thomas Corbett, 18 February 1743, requesting Bradley's attendance at the Admiralty Office.

8. Letter from John Bradley, 28 February 1743, explaining his lack of success in observing the comet.

9. Various calculations.

10. Letter from John Bradley, 13 March 1743, on the general conditions for his observations.

11. Letter from John Bevis, 17 November 1743, wishing to compare observations of Mercury's late transit. The letter outlines his observational technique and includes his findings.

12. Undated letter from John Periam of Somerset on the comet he has recently observed, with general comments on the nature of comets and their religious connotations.

13. Letter from Richard Bates of Cardiff, 1743, asking for information to improve his line of collimation, with observations.

14. Letter from Richard Bates of Cardiff, 27 August 1746, on his observations of Mercury and asking Bradley's advice on the construction of a grid iron pendulum.

15. Letter from Joseph Pollock, London, 16 June 1749, requesting information on the Moon's distance from the Greenwich Meridian on behalf of the Earl of Macclesfield. On the verso is an equation concerning light rays.

16. Letter, in Italian, from Julius Ascetto of Turin, 1750, concerning the recent lunar eclipse.

17. Letter, 15 May 1752, enclosing papers on astronomy researched by J. Rogers of Bolton, Lancashire (the papers are not included).

18. Various calculations.

19. Letter from Richard Heaton, 27 July 1752, on the position of the poles and the implications of his computations on lines of longitude and latitude for the benefit of navigators.

20. Letter from Richard Heaton, 26 August 1752, concerning his invention of a planisphere and its implications for the safety of sailors, with a direct comparison of the state of science in the mid-18th century with that of classical Greece.

21. Covering letter from Emanuel Mendes da Costa, London, 3 August 1753, on meteorological observations and lunar and solar eclipses.

22. Letter from Gael Morris, 6 May 1754, concerning zenith distances.

23. Letter from Thomas Cooke, 9 May 1754, analysing the difference between physical laws and the natural order as laid down by God.

24. A letter from Thomas Cooke, 15 August 1754, on the conflict between astronomy and theology, enclosing a piece on the precession of the equinoxes.

25. Letter from John Kennedy, 19 November 1755, requesting information on the measurement of the solar year.

26. Letter from Mr M. Roper, 5 December 1755, requesting observations before June 1743 and highlighting the errors of his own observations at that time.

27. Equation and method to find the Earth's orbit around the Sun.

28. Letter from James Stewart Mackenzie of Ham, Surrey, 5 October 1757, disputing Bradley's calculations for measuring the altitude of the Sun.

29. Letter from Contianus Liber, 10 March 1759, concerning observations and comments on the Milky Way.

30. Letter from Thomas Stevenson, Barbados, 30 June 1759, on the observations of Halley's Comet from Barbados in 1759. The letter provides details of the comet's orbit and predicts its return in 1833. There is a table of the returns of Halley's Comet, 1305-1833.

31. Further observations of Halley's Comet from Barbados by Thomas Stevenson, March - June 1759, with details of its position and the technique employed to trace its path.

32. Letter from John Fletcher of Halling, Gloucestershire, 10 January 1760, requesting an interview with Bradley to discuss the calorific efficiency of fires.

33. Letter from Christopher Irwin, 6 February 1760, concerning the Sun's orbit and observations of the Moon.

34. Letter from Stephen Hales of Teddington, 25 November 1760, requesting that Bradley act as an intermediary between him and a wealthy heiress, Mrs Mathews of Petersham, Richmond. The letter also explains his proposals for improving ventilation in ships.

35. Letter from Samuel Smedhurst of Manchester, 9 January 1762, on the transit of Venus and the difference in longitude between Manchester and London.

36. Comparative study of observations of an eclipse of Jupiter taken at London and Manchester, 1761.