Vimy Ridge and Geophysics

Vimy Ridge in northern France, a heavily fortified German army stronghold since 1914, was thought to be impregnable after large French and British armies suffered heavy losses in 1915 and 1916 in attempts to re-capture it. Many of the losses were due to their own inaccurate artillery fire. During April 9-12, 1917, the Canadian Corps under Julian Byng and Arthur Currie took Vimy Ridge, after extensive planning, preparations, and practice. Accurate control of heavy guns was important in the victory and technology was the key. German forces did not have similar technology despite efforts by a pioneer German seismologist, Ludwig Mintrop, to promote his ideas to the generals.

World War One saw the first use of airborne photography for mapping in battle. The main use of the Sopwith Camel and other early aircraft was photography. Accurate topographic maps are needed for accurate artillery

Counter Battery Officer Andrew McNaughton used early electronics equipment to perfect sound ranging and flash spotting methods to exactly locate enemy cannon on a map grid. McNaughton brought in famous British scientists, Bragg, Darwin, Bull and Canadian Harold Hemming to develop the technology on the battlefield. Sound ranging uses air waves, and flash spotting uses visual angles to triangulate on the gun locations. Source location technology predated modern computer methods for locating earthquakes.

Heavy guns were calibrated with electronics so they could hit enemy targets from map coordinates on the first shot but artillery officer’s culture had to change to accept the new technology. Wear on the gun barrel, topography, wind and weather had to be considered. A new design of artillery fuses cut barbed wire defenses allowing infantry to advance across No-Man’s-Land. Geophones and electromagnetic sensors, a pre-cursor of EM methods, were used to spy on enemy communication.

Victory at Vimy Ridge depended on accurate control of heavy guns and machine guns, a well-trained and practiced infantry, and a precisely timed battle plan. Most of the ridge was taken on the first day with soldiers following a “Creeping Barrage”, the heaviest bombardment in history. There were few Canadian casualties compared to French and British casualties at Vimy over the preceding two years. The battle of Vimy Ridge was a defining moment in the history of the young Canadian nation.