Sheet 4, Saint Omer, Carte Géologique Détaillée de la France, 1898. Scale 1:80,000.
Sheet 4, Saint Omer, Carte Géologique Détaillée de la France, 1898. Scale 1:80,000. Colour print, 61.5 x 116.5cm, cut, mounted on linen and folded to 20.5 x 13cm with explanatory notes on end margins. Belgium in NE is not coloured. Cover is slightly soiled from handling but the map is clean, bright and in very good condition.