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Keywords from Image Description:
Pigeoncameras. Julius Neubronner's tiny cameras strapped to homing pigeon Pigeoncameras UTC Pigeoncameras Julius Neubronner Original uploader was Jennavecia at org en source was loc gov Later version were uploaded by Hans Adler at org en derivative work Andibrunt talk cropped image Andibrunt Pigeoncameras PDold