Greenwich Mean Time

“For every 15 degrees of longitude made good to the westward the ship's clocks were put back an hour — they were already two hours earlier than Greenwich Mean Time when Wattenberg noted in the log on 27th August that the Graf Spee was now on the same latitude as London, in a position almost midway between Britain and Newfoundland.”

Graf Spee

“A further radio message, very broken and difficult to decipher, was received 0945 Greenwich Mean Time from Drift Ice Station Zebra by the British trawler Morning Star, the vessel that picked up the previous broadcast.”

Ice Station Zebra