Ordnance survey of Scotland.
Southampton : Ordnance Survey Office,
1856-1887.
Surveyed 1845-78.
Wanting maps 69 and 70.
There is an extra map 57A.
Maps are in either of 2 versions - relief shown by hachures (Lowlands and Grampians), or contours (North-West and Islands, ex Lewis).
Census Office.