The numbers of the enemy seemed no less formidable during the night than by the light of day; far and wide their watch-fires were to be seen gleaming over valley and hill-top, as thickly scattered, says an eyewitness, as "the stars of heaven in a cloudless summer night." 8 Before these fires had become pale in the light of the morning, the Spaniards were roused by the hideous clamor of conch, trumpet, and atabal, mingled with the fierce war-cries of the barbarians, as they let off volleys of missiles of every description, most of which fell harmless within the city. But others did more serious execution. These were burning arrows, and redhot stones wrapped in cotton that had been steeped in some bituminous substance, which, scattered long trains of light through the air, fell on the roofs of the buildings, and speedily set them on fire.9 These roofs, even of the better sort of edifices, were uniformly of thatch, and were ignited as easily as tinder. In a moment the flames burst forth from the most opposite quarters of the city. They quickly communicated to the wood-work in the interior of the buildings, and broad sheets of flame mingled with smoke rose up towards the heavens, throwing a fearful glare over every object. The rarefied atmosphere heightened the previous impetuosity of the wind, which, fanning the rising flames, they rapidly spread from dwelling to dwelling, till the whole fiery mass, swayed to and fro by the tempest, surged and roared with the fury of a volcano. The heat became intense, and clouds of smoke, gathering like a dark pall over the city, produced a sense of suffocation and almost blindness in those quarters where it was driven by the winds.10 The Spaniards were encamped in the great square, partly under awnings, and partly in the hall of the Inca Viracocha, on the ground since covered by the cathedral. Three times in the course of that dreadful day, the roof of the building was on fire; but, although no efforts were made to extinguish it, the flames went out without doing much injury. This miracle was ascribed to the Blessed Virgin, who was distinctly seen by several of the Christian combatants, hovering over the spot on which was to be raised the temple dedicated to her worship.11