Students at the University of Essex in Colchester have been given lectures 18 meters underwater. They were taught about the impact of climate change on the coral reefs off the coast of Indonesia.
Professor David Smith used specialised audio equipment to speak directly to the students underwater and describe what they were seeing.
Professor Smith wore a microphone that was inside a full face mask and students wore wireless headsets.
A hydrophone, or underwater microphone, then recorded the footage for use by students back in Essex. Fifteen hours of footage was recorded.