"It's come, Hackness," he cried. "It was bound to come sometime. It's all here in a late edition of the Telegraph. We must go and see it." He flung himself into an armchair. "Do you remember," he said, "the day in the winter of 1898, the day that petroleum ship exploded? You and I were playing golf together on the Westgate links." Hackness nodded eagerly. "I shall never forget it, Eldred," he said, "though I have forgotten the name of the ship. She was a big iron boat, and she caught fire about daybreak. Of her captain and her crew not one fragment was ever found." "It was perfectly still and the effect of that immense volume of dense black smoke was marvellous. Do you recollect the scene at sunset? It was like looking at half-a-dozen Alpine ranges piled one on the top of the other. The spectacle was not only grand, it was appalling, awful. Do you happen to recollect what you said at the time?" There was something in Eldred's manner that roused Hackness. "Perfectly well," he cried. "I pictured that awful canopy of sooty, fatty matter suddenly shut down over a great city by a fog. A fog would have beaten it down and spread it. We tried to imagine what might happen if that ship had been in the Thames, say at Greenwich." "Didn't you prophesy a big fog for to-day?" "Certainly I did. And a recent examination of my instruments merely confirms my opinion. Why do you ask?" "Because early this morning a fire broke out in the great petroleum storage tanks, down the river. Millions of gallons of oil are bound to burn themselves out--nothing short of a miracle can quench the fire, which will probably rage all through to-day and to-morrow. The fire-brigades are absolutely powerless--in the first place the heat is too awful to allow them to approach; in the second, water would only make things worse. It's one of the biggest blazes ever known. Pray Heaven, your fog doesn't settle down on the top of the smoke." Hackness turned away from his unfinished breakfast and struggled into an overcoat. There was a peril here that London little dreamt of. Out in the yellow streets newsboys were yelling of the conflagration down the Thames. People were talking of the disaster in a calm frame of mind between the discussion of closer personal matters. "There's always the chance of a breeze springing up," Hackness muttered. "If it does, well and good, if not--but come along. We'll train it from Charing Cross." A little way down the river the mist curtain lifted. A round magnified sun looked down upon a dun earth. Towards the South-east a great black column rose high in the sky. The column appeared to be absolutely motionless; it broadened from an inky base like a grotesque mushroom. "Fancy trying to breathe _that_," Eldred muttered. "Just think of the poison there. I wonder what that dense mass would weigh in tons. And it's been going on for five hours now. There's enough there to suffocate all London."