The cloud, which had scattered so deep a murkiness over the day, at length settled into a solid and impenetrable mass. But in proportion as the blackness gathered did the lightnings around Vesuvius increase in their vivid and scorching glare.
Nor was their horrible beauty confined to their hues of fire. Now brightly blue, as the most azure depth of a southern sky; now of a livid and snake-like green, darting restlessly to and fro, as the folds of an enormous serpent; now of a lurid and intolerable crimson, gushing forth through the columns of smoke far and wide, and lighting up all Pompeii; then suddenly dying into a sickly paleness, like the ghost of its own life!
In the pauses of the showers were heard the rumbling of the earth beneath, and the groaning waves of the tortured sea; or, lower still, and audible but to the watch of intensest fear, the grinding and hissing murmur of the escaping gases through the chasms of the distant mountain.
The ashes, in many places, were already knee-deep; and in some places immense fragments of rock, hurled upon the house-roofs, bore down along the streets masses of confused ruin, which yet more and more, with every hour, obstructed the way; and, as the day advanced, the motion of the earth was more sensibly felt; the footing seemed to slide and creep, nor could chariot or litter be kept steady, even on the most level ground.
Sometimes the huger stones, striking against each other as they fell, broke into countless fragments, emitting sparks of fire, which caught whatever was combustible within their reach; and along the plains beyond the city the darkness was now terribly relieved, for several houses and even vineyards had been set on flames; and at various intervals the fire rose fiercely and sullenly against the solid gloom. The citizens had endeavoured to place rows of torches in the most frequented spots; but these rarely continued long; the showers and the wind extinguished them.
Suddenly arose an intense and lurid glow. Bright and gigantic through the darkness which closed around it, the mountain shone, a pile of fire! Its summit seemed riven in two; or rather, above its surface, there seemed to rise two monster-shapes, each confronting each, as demons contending for a world. These were of one deep blood-red hue of fire, which lighted up the whole atmosphere; but below, the nether part of the mountain was still dark and shrouded, save in three places, adown which flowed serpentine, and irregular rivers of molten lava. Darkly red through the profound gloom of their banks, they flowed slowly on, as towards the devoted city. And through the still air was heard the rattling of the fragments of rock, hurling one upon another, as they were borne down the fiery cataracts, darkening for one instant the spot where they fell, and suffused the next in the burnished hues of the flood along which they floated!