An original, geological map of the southern British Isles (most of England and Ireland, and whole of Wales) by AK Johnston. The map ('Palaeontological map') was published in 1854-56 in by Wm Blackwood of Edinburgh in  Johnston's Physical Atlas of Natural Phenomena. It is unframed, unmounted, and coloured (printed area is approximately 610x520mm) and includes a detailed key to the geological systems, tables of fossil ammonites, and numerous annotations describing other fossil types. The map is in very good condition, though there are a few marginal tears, none of which affect the printed area.