ADMIRALTY HYDROGRAPHIC OFFICE
South Atlantic Ocean Island of St. Helena from a Survey by Captn. Edmund Palmer, R.A. 1852. The Soundings from a Survey by George Thoms, Master HMS Northumberland, 1816. The North West Bank of Soundings by Captn. F.W. Austen R.N. 1808 ...
Although this was published by the Admiralty, it is a detailed map of the island, highlighting the rocky interior, with detailed soundings for the north-western coast, notably for James Bay.
The map marks ‘The Briars Napoleon’s first Residence’ as also Longwood House.