Plate, contoured plan of Arthur's Seat by unknown mapmaker Contoured plan of Arthur's Seat in Edinburgh, Scotland, with the zenith sector stations and lines of section marked in red ink. Subject: Geodesy Published in Philosophical Transactions as 'On the deflection of the plumb-line at Arthur's Seat, and the mean specific gravity of the earth'. Received by the Royal Society on 11 February 1856. Read 21 February 1856. [1856]