'Trench Warfare in the Argonne', (1919). Scene from the First World War, 1914-1919: 'The French infantry displayed considerable ingenuity in the construction of trench mortars made from unexploded German shells, from which they fired bombs into the German trenches. In this photograph two of these mortars have just been fired and two others are seen about to be discharged.' From "The History of the Great European War: its causes and effects", Vol. IV, by W. Stanley Macbean Knight. [Caxton Pulishing Company, Limited, London, 1919]