Mt. Vesuvius, the volcano that destroyed Pompeii and Herculaneum in A.D. 79, is the icon of power and energy in this work. The tension and suspense of the impending cataclysm characterizes the introduction of the main themes. Driving rhythms and complex mode changes convey a bacchanalian mood that is interrupted by quotations from the Dies Irae of the medieval Requiem Mass, invoked as a symbol of death and destruction. An image of everyday village life in the towns oblivious to the danger, portrayed in a quiet interlude, is disturbed by the first fiery events on the mountain. A final battle of themes builds to a state of extreme agitation, conveying the chaos of the pyroclastic explosions and suffocating ash.