Anon. (1920). Special Reports on the Mineral Resources of G.B.: Vol. VI- Refractory Materials: Ganister and Silica-Rock – Sand Reproduction later the Royal Engineers assisted

later the Royal Engineers assisted the Ordnance Survey with the primary triangulation of the British Isles

issued 1893

No issue stamp

The map is very slightly soiled and slightly worn at the intersection of some folds

Currently (2024) no memoir - covered only as brief explanation booklet accompanying map

Anon. (1920). Special Reports on the Mineral Resources of G.B.: Vol. VI- Refractory Materials: Ganister and Silica-Rock – Sand Reproduction later the Royal Engineers assistedAnon. (1920). Special Reports on the Mineral Resources of G. B.: Vol. VI Refractory Materials: Ganister and Silica Rock Sand for open Hearth Steel Furnaces Dolomite. Resources and Geology. London: Geological Survey, 2nd edition. 241+ vi pp. Three fold out b w maps. Paperback. Worn, with front cover detached. Binding sound, clean text. Signature of owner on front cover. In fair condition.