'The Magnetic Clock, Greenwich Observatory', c1840, (c1878). People looking at the Shepherd Gate Clock on the wall outside the gate of the Royal Observatory at Greenwich in south London. The clock, constructed and installed by Charles Shepherd in 1852, was probably the first to display Greenwich Mean Time to the public. From Old and New London: A Narrative of Its History, Its People, And Its Places. The Southern Suburbs, Volume VI, by Edward Walford. [Cassell, Petter, Galpin & Co., London, Paris & New York, c1878]