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The Obliquity of the Ecliptic, 1807

Reference Code: GBR/0180/RGO 4/180

Scope and Contents

'Of the Obliquity of the Ecliptic', a memoir by Guiseppe Piazzi, translated by Margaret Maskelyne in 1807 from Piazzi's 'Dell' Obliquita dell' eclittica'.

1. Zenith distance of the Sun by the satellites observed at Palermo, 1794-1803.

2. Obliquity of the ecliptic reduced from arithmetical observations, 1791-1803.

3. Obliquity of the ecliptic reduced from the Greenwich observations by Maskelyne, 1790-1799.

4. Difference of the obliquity of the summer and winter solstices.

5. The solstices at Palermo and Greenwich compared together.

6. Correction for the nutation depending on the perihelion of the Moon.

7. Mean obliquity of the ecliptic for 1800.

8. Annual decrease of the obliquity of the ecliptic.

9. 'Value of the nutation of the axis of the Earth passing the lunar node with a retrogate motion from the first of Libra to the first of Aries.'

10. Supplement to Piazzi's memoirs of the obliquity of the ecliptic, taking the observations up to 1804.


  • Creation: 1807


Conditions Governing Access

From the Management Group:

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1 envelope(s) (1 envelope)

Language of Materials


Former / Other Reference


Finding aid date

2005-11-07 10:57:55+00:00

Includes index.


Repository Details

Part of the Cambridge University Library Repository

Cambridge University Library
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Cambridge CB3 9DR United Kingdom