October 15, 1910 Sporting Life
http://library.la84.org/SportsLibrary/SportingLife/1910/VOL_56_NO_06/SL5606023.pdf
The newest thing in the line of firearms is a featherweight shotgun of 20 bore being manufactured by the Ithaca Gun Company, of Ithaca, N. Y., for use in an aeroplane. This is a new departure, the order having been received from a New England man who desires to try water fowl shooting from his aircraft.

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