Sheet 59, Old Series 1". Early 1850s. Cardiganshire: Barmouth, Dolgelly, Machynlleth. Hand-coloured
Sheet 59, Old Series 1". Early 1850s. Cardiganshire: Barmouth, Dolgelly, Machynlleth. Hand-coloured engraving, 71.5 x 99.5cm, four quarter sheets dissected, mounted on linen, and folded to 24 x 16.5cm with index map pasted on top outside fold. Topographic date1837 for SW and SE quadrants. Issue date 1854 for NW quadrant. No geological dates on SW and SE quadrants. Some dates lost in the joining of the four quarters. Legend for NE quadrant only. The west half of the assembled is almost entirely Cardigan Bay but for a chain of small islets,so these two quarter sheets were not generally purchased. The assemblage is rare. Clear plate marks, Clean, bright colours. In fine condition.
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.