Trevor Norton, whose first book, Stars Beneath the Sea (1999), won him the accolade "Bill Bryson underwater" is professor of Marine Biology at the University of Liverpool and director of the Port Erin Marine Laboratory on the Isle of Man. He has written numerous scientific publications, and is an authority on the history of scientific diving. This extract is from his latest book, Reflections on a Summer Sea (Century, £12.99 in UK), published last week, and illustrated with line drawings by his wife, Win. The book was inspired by the many summers Norton spent researching marine life at Lough Ine during the 1960s and 1970s. Lough Ine is a marine lough in West Cork, also known as Lough Hyne.