'Map To Illustrate the German Submarine Blockade and the British Minefields as a Measure of Protection', 1919. Map of the Atlantic Ocean during the First World War, 1914-1919, showing part of the east coast of the United States, Great Britain and western Europe. From "The History of the Great European War: its causes and effects", Vol. VII, by W. Stanley Macbean Knight. [Caxton Pulishing Company, Limited, London, 1919]