The water had been consumed, as though it were straw, and not a drop remained.  She passed her hand absently across her forehead.

‘But water cannot burn,’ she muttered to herself.

It seemed that Haddo knew what she thought, for he smiled strangely.

’Do you know that nothing more destructive can be invented than this blue powder, and I have enough to burn up all the water in Paris?  Who dreamt that water might burn like chaff?’

He paused, seeming to forget her presence.  He looked thoughtfully at the little silver box.

’But it can be made only in trivial quantities, at enormous expense and with exceeding labour; it is so volatile that you cannot keep it for three days.  I have sometimes thought that with a little ingenuity I might make it more stable, I might so modify it that, like radium, it lost no strength as it burned; and then I should possess the greatest secret that has ever been in the mind of man.  For there would be no end of it.  It would continue to burn while there was a drop of water on the earth, and the whole world would be consumed.  But it would be a frightful thing to have in one’s hands; for once it were cast upon the waters, the doom of all that existed would be sealed beyond repeal.’

He took a long breath, and his eyes glittered with a devilish ardour.  His voice was hoarse with overwhelming emotion.

’Sometimes I am haunted by the wild desire to have seen the great and final scene when the irrevocable flames poured down the river, hurrying along the streams of the earth, searching out the moisture in all growing things, tearing it even from the eternal rocks; when the flames poured down like the rushing of the wind, and all that lived fled from before them till they came to the sea; and the sea itself was consumed in vehement fire.’

Margaret shuddered, but she did not think the man was mad.  She had ceased to judge him.  He took one more particle of that atrocious powder and put it in the bowl.  Again he thrust his hand in his pocket and brought out a handful of some crumbling substance that might have been dried leaves, leaves of different sorts, broken and powdery.  There was a trace of moisture in them still, for a low flame sprang up immediately at the bottom of the dish, and a thick vapour filled the room.  It had a singular and pungent odour that Margaret did not know.  It was difficult to breathe, and she coughed.  She wanted to beg Oliver to stop, but could not.  He took the bowl in his hands and brought it to her.

‘Look,’ he commanded.

She bent forward, and at the bottom saw a blue fire, of a peculiar solidity, as though it consisted of molten metal.  It was not still, but writhed strangely, like serpents of fire tortured by their own unearthly ardour.

‘Breathe very deeply.’