December 21 marked 150 years since HMS Challenger set sail to map the world’s seas - and it couldn't have done so without Edinburgh.
The HMS Challenger set off from Portsmouth harbour in 1872 and was the first to explore the the depths of the oceans globally and in turn revolutionised the field of oceanography.
But as research from Edinburgh University shows, it really couldn't have happened without Edinburgh. To explore the seven seas, the Royal Society appointed West Lothian born Charles Wyville-Thomson to lead the team of scientists. He was a 'veteran' of several shorter expeditions out at sea and recently received the the natural history chair at the University of Edinburgh.