By Fred Pearce: Lanzarote, an island off the west coast of Africa, was a tranquil place in the eighteenth century, ruled by Spanish priests and visited occasionally by ships making the transatlantic crossing. Farming was rudimentary and the living poor. The island had less rain than much of the Sahara desert. Then came a series of massive volcanic eruptions that shook the island almost without a break from 1730 to 1735. A priest described how, at the height of the eruptions, “the earth suddenly opened… a gigantic mountain rose and sank back into its crater on the same day, covering the island with stones and ashes”.