Sheet 60ne, Old Series 1". 1852. First edition. Mid Wales: Montgomeryshire: Welshpool. Hand coloured engraving
Sheet 60ne, Old Series 1". 1852. First edition. Mid Wales: Montgomeryshire: Welshpool. Hand coloured engraving, flat, 40x 56cm. Topography 1836, geology date omitted issued 1852. Clear plate mark. Upper left corner clipped and a tear in top margin, neither into the plate area. Clean, bright and in very good condition.
The colour selection is from an earlier specification, found on the earliest maps of Cornwall and Mid Wales, preceding the more familiar standard legend that soon followed. Principally, a pale green is used for alluvium and dark green and and green are used for igeneous rocks that are now coloured shades of purple, orange, and red.The usual ‘first edition’ maps in this area give the geological mapping dates as a range such as 1853/55 and have a slightly expanded legend. On this map which omits the geological dates, we take it as 1852 in view of the issue date of embossed stamp in the top right corner. RARE
About the England & Wales One Inch Old Series
The Geological Survey of England and Wales used the Old Series of the Ordnance Survey topographic map at a scale of one inch to the mile as its basemap, initially. These engraved basemaps were published and revised between 1805 and 1885; the sheet sizes varied and the layout and numbering system were eccentric. The Old Series geological maps were hand-coloured and without geological sections, which were published separately. The GS of E&W published the Old Series from 1850 to 1900, when it switched to the colour printing and the New Series one inch maps. However, old stock of the Old Series continued to be issued, hand-coloured, until the 1930s.