But the lights were merely being wrapped in a filament that every moment grew more and more dense. As the curtain went up again there was just the suspicion of a draught from the back of the stage, and the whole of it was smothered in a small brown cloud that left absolutely nothing to the view. It was impossible now to make out a single word of the programme, even when it was held close to the eyes.

"Hackness was right," Grimfern growled. "We had far better have stayed at home."

Hackness said nothing. He had no pride in the accuracy of his forecast. Perhaps he was the only man in London who knew what the full force of this catastrophe meant. It grew so dark now that he could see no more than the mere faint suggestion of his fair companion, something was falling out of the gloom like black ragged snow. As the pall lifted just for an instant he could see the dainty dresses of the women absolutely smothered with the thick oily smuts. The reek of petroleum was stifling.

There was a frightened scream from behind, and a yell out of the ebony wall to the effect that somebody had fainted. Someone was speaking from the stage with a view to stay what might prove to be a dangerous panic. Another sombre wave filled the theatre and then it grew absolutely black, so black that a match held a foot or so from the nose could not be seen. One of the plagues of Egypt with all its horrors had fallen upon London.

"Let us try and make our way out," Hackness suggested. "Go quietly."

Others seemed to be moved by the same idea. It was too black and dark for anything like a rush, so that a dangerous panic was out of the question. Slowly but surely the fashionable audience reached the vestibule, the hall, and the steps.

Nothing to be seen, no glimmer of anything, no sound of traffic. The destroying angel might have passed over London and blotted out all human life. The magnitude of the disaster had frightened London's millions as it fell.

III.

A city of the blind! Six millions of people suddenly deprived of sight!

The disaster sounds impossible—a nightmare, the wild vapourings of a diseased imagination—and yet why not? Given a favourable atmospheric condition, something colossal in the way of a fire, and there it is. And there, somewhere folded away in the book of Nature, is the simple remedy.