This graphic has been making the rounds at several websites and forums
recently.  It's from the book "America's Munitions 1917-18" by Benedict
Crowell and apparently shows the sound of the end of WWI:

http://life.time.com/history/world-war-i-ceasefire-november-11-1918-graphic/#1

From my limited Googling around, this appears to have been created by a
military sound ranging system using low frequency microphones that was in
development during the War.

http://en.wikipedia.org/wiki/Sound_ranging#World_War_I

Are there any more original examples of these recordings that survive in
their original form and not as reproductions in books?  Patrick Feaster
know about this?

rand

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Randy A. Riddle
www.coolcatdaddy.com