Digital Images Archive
97. One-inch New Popular Edition sheet 167, with an experimental graticule reference system, 1945 (CCS 218B/49/8)
Experimental versions of one-inch New Popular Edition sheet 167 Salisbury and 1:25,000 Larkhill and Westdown were printed for artillery training with a graticule referencing system in place of a grid. This is based on sectors of 5º of latitude and 5º of longitude, each given a single letter reference (in this case F), the 25 1º subdivisions being identified by a second letter. Thus the 51º N, 2º W zone containing Salisbury has the letter reference FT. There were three trial variants of the one-inch sheet, printed by the Ordnance Survey in November 1945:
1. With a mesh in 100th of degrees overprinted in purple (the image reproduced here).
2. With a mesh in 100th of degrees and partial ladder, overprinted in purple.
3. With a minute mesh and partial ladder, overprinted in purple. The published version was entitled D.R.A.'s investigation of graticules. It has a minute mesh in black, and a print code 500/11/45 Cr.
From a copy now transferred to Cambridge University Library