This account of the greatest lava flow in historical times, which occurred in Iceland only two hundred years ago, is a unique eye-witness record of a dramatic natural catastrophe which threatened the lives of a small nation in the high north. It was the Reverend Jon Steingrimsson, a living legend in his day for a sermon said to have halted the glowing molten lava as it cascaded towards his church, who described this merciless outburst of nature's fury. His original observations and insights make this work at once a scientific classic and a literary gem.