Geological Survey of Great Britain (England and Wales) Great Britain. Ordnance Survey. Sheet 336 solid and drift. North Decimal Degree 50.6500. South Decimal Degree 50.4833. East Decimal Degree -4.5333. West Decimal Degree -4.9500. Relief shown by contour interval and spot heights.Transverse Mercator projection. National grid system. Depth is shown by contour interval. "Original Geological Survey, on the one-inch scale, by Sir H. T. De la Beche, F.R.S. Published on Sheet 30, Old Series. Resurved on the six-inch scale by Clement Reid et al. Part of the northern area revised by M. C. Mc Keown and G. Bisson in 1964.".