"PUBLIC WARNING" poster printed by Sir Joseph Causton, London, as authorized by Her Majesty's Stationery Office, 1915. This poster was found occasionally 40 years ago but has become quite scarce today. This is only the third one I have had and one is in my collection. This poster is about very good, overall age toning, one horizontal fold and a small rub in lower right margin. Really a "must" in the WWI aero collector's "cave".