About eight o'clock
Three seconds had elapsed since the violet-gray cloud of fury struck the town , but in those three seconds 30,000 people lay dead , slain with such appalling swiftness that none knew their fate . No one had tried to escape . The eruption was witnessed , from a distance , by only one trained observer , Roger Arnoux , and a translation of his record is , in part , as follows : `` Having left St. Pierre at about five in the evening -LRB- May 7 -RRB- I was witness to the following spectacle : Enormous rocks , being clearly distinguishable , were being projected from the crater to a considerable elevation , so high , indeed , as to occupy a quarter of a minute in their flight . `` About eight o'clock of the evening we recognized for the first time , playing about the crater , fixed fires that burned with a brilliant white flame . Shortly afterwards , several detonations , similar to those that had been heard at St. Pierre , were noted coming from the south , which confirmed me in my opinion that there already existed a number of submarine craters from which gases were being projected , to explode when coming in contact with the air . `` Having retired for the night , at about nine o'clock , I awoke shortly afterwards in the midst of a suffocating heat and completely bathed in perspiration ... . I awoke again about eleven thirty-five , having felt a trembling of the earth ... but again went to sleep , waking at half-past seven .