A retired chemist from Potenza, on the other hand, visiting the capital for only the second time in his life, recalled the earthquake which had recently devastated his own city and saw a chunk of the dome plummeting down, first token of a general collapse. Others thought confusedly of spiders or bats, super-hero stunts or circus turns. Only one observer knew precisely what was happening, having seen it all before. Giovanni Grimaldi let go of the nun’s bouquet of flowers, which scattered on the marble floor, and reached for his two-way radio.

Subsequent calculations demonstrated that the period of time elapsing between the initial sighting and terminal impact cannot have exceeded four seconds, but to those watching in disbelief and growing horror it was a period without duration, time-free. The figure might have been falling through a medium infinitely more viscous than air, so slowly did it appear to descend, revolving languidly about its own axis, the long sustained keening wrapped around it like winding robes, the limbs and trunk executing a leisurely sarabande that ended as the body smashed head first into the marble paving at something approaching seventy miles per hour.

No one moved. The glistening heap of blood and tissue subsided gently into itself with a soft farting sound. Priest and congregation, tourists and attendants, stood as silent and still as figures in a plaster Nativity. In distant nooks and crannies of the vast enclosure, the final echoes of that long scream died away. Then, as strident as trumpets, first one, them many voices took up the strain, shrieking hysterically, howling, sobbing and gasping.

Giovanni Grimaldi started towards the body. It seemed to take for ever, as in a bad dream, the crowd perpetually closing up right in front of him, denying him passage. Then he was through the inner circle, beyond which no one was prepared to go, and promptly slipped and fell, his radio dropping with a loud clatter.