In keeping with the maritime flavour of the day, we traveled from Bankside Pier near Tate Modern to Greenwich by a very comfortable riverboat to visit the maritime installations at Greenwich.
Highlights included the National Maritime Museum, a veritable cornucopia of marine history and artefacts, including Turner’s famous large painting of the Victory at Trafalgar. Some of us visited a separate building, originally designed as a refectory, with its magnificent painted ceiling in a process of restoration,
The Greenwich Observatory featured the accurate measurement of time, particularly to measure longitude on the high seas, as well as various telescopes to observe the night sky. The most accurate clocks were designed by John Harrington and helped to make Greenwich the place of zero longitude, a much contested location.
Of course, we had to test the location with mobile phones and my iPhone gave the result shown (inset below), some 5 seconds or about 100m to the west of the Prime Meridian because GPS derived longitudes are affected by the shape of the Earth. The ball at the top of the building (arrowed below) was (and still is) dropped at exactly 1 pm every day to enable ships in former times to set their clocks before a voyage.
Refreshed at the Museum cafe, we made our way back to Blackfriars for Thameslink services by the Docklands Light Railway. Sorry, no group photo this time.