Damaged railway tracks, Zhabei, Shanghai, 1932

Radio aerial made by Jack Ephgrave, Shanghai

Radio aerial made by Jack Ephgrave, Shanghai

Phil Blown with amateur (ham) radio equipment, Shanghai

Phil Blown with amateur (ham) radio equipment, Shanghai

American Marines with signal equipment and semaphore flags on a rooftop lookout, Shanghai

American Marines with signal equipment and semaphore flags on a rooftop lookout, Shanghai

American Marines with signal equipment and semaphore flags on a rooftop lookout, Shanghai

Fires burning near Shanghai North Railway Station signal box, Zhabei, 1937

Shanghai North Railway Station signal cabin taken over by Japanese Marines, October 1937

Shanghai North Railway Station, Zhabei, October 1937

Signal Station, Victoria Peak, Hong Kong

Old Chinese war telegraph (signal towers), Nankou Pass (南口关), near Beijing

Rigging with signal flags, Shanghai

Rigging with signal flags on sailing ship, Shanghai

North China British Volunteers, with signal flags, Peking