From the
New York Times of 21 August 1914:
wATCH SKY FOR MESSAGES
British Public Told to be on Lookout for Aeroplane Notes
LONDON, Aug. 20.--- Aeroplanes now are playing the part in war which formerly only carrier pigeons could perform, and seem to have greater possibilities than pigeons.
An official notification issued tonight to the people of England requests them to be watchful for messages dropped from aeroplanes, describes the peculiar wrappings which will inclose messages and instructs the finders to forward them immediately to the addresses they bear.
French aeroplanes scattered messages to the inhabitants of Alsace in the early days of the war, and the Russians adopted the same method for announcing the proclamation of Emperor Nicholas to the Poles.
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