Sgt. McGarrigle is seen in this photograph taken on November 6, 1918, working with a wave meter used by the Signal Corps. The wave meter is a mechanism manufactured by the General Radio Co. in Cambridge, Massachusetts. This image is not meant for publication and is marked for official use only. (50 words)

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Size: 8370px × 5643px
Photo credit: © piemags/NSC / Alamy / Afripics
License: Licensed
Model Released: No

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