United Kingdom. Ministry of Defence. Directorate General of Military Survey. Great Britain. Directorate of Military Survey. North Decimal Degree 17.500000. South Decimal Degree 17.2500. East Decimal Degree -88.5000. West Decimal Degree -88.7500. Standard map series designation: Series E755 (D.O.S. 4499). Transverse Mercator projection. U.T.M. zone 16 grid. Relief shown by 40 m. contour interval, shading and spot heights.