Original geological survey on the one-inch scale by Sir H.T. De la Beche, Director General, W.T. Aveline and others. Published on Sheets 20 and 36 Old Series. Revisions up to 1878 by H.W. Bristow and H.B. Woodward. Resurveyed on the six-inch scale by A. Strahan, M.A. and T.C. Cantrill, B.Sc. (western margin). Published with Drift July 1897. Revised 1902. Published in color by the Director General Ordnance Survey 1903. Vertical and horizontal folds.
Approx 50cms by 33cms
