Unpublished diagram, plane of the meridian by [Thomas Kerigan] Diagram showing the plane of the meridian at a given point of observation, with the earth's axis, equator, horizon, prime vertical, and latitude delineated. Subject: Geodesy / Astronomy Written by Kerigan in Portsea [Porstmouth, England]. Communicated by Sir Edwd [Edward] Codrington. Received by the Royal Society from the President [Augustus Frederick] on 18 February 1832. Read 15 March 1832. Whilst the Royal Society declined to publish this paper in full, an abstract of the paper was published in volume 3 of Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London [later Proceedings of the Royal Society] as 'A method of deducing the longitude from the moon’s right ascension'. 28 January 1832