Science  /  Retrieval

Powers of Hearing: The Military Science of Sound Location

During WWI the act of hearing was recast as a tactical activity — one that could determine human and even national survival.

According to “The End of the War: A Graphic Record,” the frontispiece of a towering report commissioned by the U.S. Assistant Secretary of War during WWI, the Great War ended not with a bang, but, as in the famous verse, a whimper.

The image, which showed six horizontal lines on a filmstrip, depicted artillery activity at the American front near the Moselle River exactly one minute before and one minute after the time of armistice, 11:00 a.m. on November 11, 1918. The left side depicted artillery activity at one minute before armistice and showed a flurry of jagged lines (“All guns firing”). On the right side, which depicted artillery activity at one minute after armistice, there were only smooth lines (“All guns silent”). Two small dips around 11:01:01 were attributed to the exuberance of a doughboy who fired his pistol twice in celebration of the ceasefire. Apart from these gunshots, it appeared that artillery activity had ceased entirely, and that the battlefield had been suddenly drained of the throttling sounds of gunfire.

The caption for “The End of the War” stated that it was the last record of artillery activity at the American front, and that the image issued from an American sound ranging apparatus. “Sound ranging,” it read, “was an important means of locating the positions and calibers of enemy guns.” When the image was reproduced in the Journal of Electricity the claims made about it were even grander: “Truly history has here been written electrically!”

“The End of the War” was produced through one of numerous methods of acoustic defense that were invented during the First World War. At the outset of the war the concept of acoustic defense was mostly unknown. None of the principal armies possessed reliable means for tracking the position of the enemy by following the sounds it made. By the end of the war, however, each had developed new technologies and techniques for sound location, typically in response to new technologies of offense, and each had employed these methods on countless occasions — thereby generating new modes of “acoustic defense.”