Photographs and Photocopies

Undated photocopies of letters from Nevil Maskelyne to James Stuart Mackenzie:

(1) 19 August 1790, giving Mackenzie the rule for determining the time which the Moon's semi-diameter takes to pass the meridian, 2 pages.

(2) 2 November 1790, regarding the measurement of the distance of the Moon's east and west limit from the meridian, 3 pages.

(3) 4 November 1790, providing additional information on a method of observing the right ascension of the Moon using the equatorial instrument, 2 pages.

(4) 31 December 1790, describing Ramsden's method of determining the longitude of an observing site and discussing in detail the use of the equatorial instrument, 3 pages.

Indexed