Amidst the other horrors, the mighty mountain now cast up columns of boiling water.  Blent and kneaded with the half-burning ashes, the streams fell like seething mud over the streets in frequent intervals.  And full, where the priests of Isis had now cowered around the altars, on which they had vainly sought to kindle fires and pour incense, one of the fiercest of those deadly torrents, mingled with immense fragments of scoria, had poured its rage.  Over the bended forms of the priests it dashed:  that cry had been of death—­that silence had been of eternity!  The ashes—­the pitchy streams—­sprinkled the altars, covered the pavement, and half concealed the quivering corpses of the priests!

‘They are dead,’ said Burbo, terrified for the first time, and hurrying back into the cell.  ‘I thought not the danger was so near and fatal.’

The two wretches stood staring at each other—­you might have heard their hearts beat!  Calenus, the less bold by nature, but the more griping, recovered first.

‘We must to our task, and away!’ he said, in a low whisper, frightened at his own voice.  He stepped to the threshold, paused, crossed over the heated floor and his dead brethren to the sacred chapel, and called to Burbo to follow.  But the gladiator quaked, and drew back.

‘So much the better,’ thought Calenus; ‘the more will be my booty.’  Hastily he loaded himself with the more portable treasures of the temple; and thinking no more of his comrade, hurried from the sacred place.  A sudden flash of lightning from the mount showed to Burbo, who stood motionless at the threshold, the flying and laden form of the priest.  He took heart; he stepped forth to join him, when a tremendous shower of ashes fell right before his feet.  The gladiator shrank back once more.  Darkness closed him in.  But the shower continued fast—­fast; its heaps rose high and suffocatingly—­deathly vapors steamed from them.  The wretch gasped for breath—­he sought in despair again to fly—­the ashes had blocked up the threshold—­he shrieked as his feet shrank from the boiling fluid.  How could he escape? he could not climb to the open space; nay, were he able, he could not brave its horrors.  It were best to remain in the cells, protected, at least, from the fatal air.  He sat down and clenched his teeth.  By degrees, the atmosphere from without—­stifling and venomous—­crept into the chamber.  He could endure it no longer.  His eyes, glaring round, rested on a sacrificial axe, which some priest had left in the chamber:  he seized it.  With the desperate strength of his gigantic arm, he attempted to hew his way through the walls.

Meanwhile, the streets were already thinned; the crowd had hastened to disperse itself under shelter; the ashes began to fill up the lower parts of the town; but, here and there, you heard the steps of fugitives cranching them warily, or saw their pale and haggard faces by the blue glare of the lightning, or the more unsteady glare of torches, by which they endeavored to steer their steps.  But ever and anon, the boiling water, or the straggling ashes, mysterious and gusty winds, rising and dying in a breath, extinguished these wandering lights, and with them the last living hope of those who bore them.