Other applications are listed below Pelorus or Dumb Plate. Marked AM (Air Ministry) - 6B 213, W.G.P Ltd. These bearings are simultaneously compared to the vessel’s compass heading which then gives the compass bearing to the object.
Vintage Maritime Brass Nautical Sextant Leather Case Kelvin Hughes London 1917
VINTAGE MARITIME INTERNATIONAL CODE OF SIGNALS BOOK, H.M.S.O, 1969, ROYAL NAVY
