As you will see in this detail taken from his etching, which was turned into a watercolour by another artist later that century, the great illuminated cross was suspended before the altar and confessio of basilica. In this particular detail, one can see the pope, dressed in choir dress, kneeling before the cross.
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| Detail from an etching originally by Giovanni Battista Piranesi (1720-1778). Watercolour version by Louis Jean Desprez (1798). |
This cross, which was comprised of 628 lights, was placed so within the basilica on Holy Thursday, presumably following the stripping of the altar on Holy Thursday where it remained through Good Friday.
Writing in 1839 in his work, The Ceremonies of Holy Week at the Vatican and St. John Lateran's Described, C.M. Baggs comments on this custom (by then lost):
It is much to be regretted that the cross, which used on Holy Thursday and Good Friday to glow with 628 lights, and to produce a splendid effect by the chiaroscuro [LAJ: a strong contrast between light vs. dark; in this instance the contrast between the light of the illuminated cross versus the darkened basilica of St. Peter's] which resulted from it in this vast and magnificent fabric, is no longer suspended before the Confession in consequence of irreverent conduct on preceding occasions.
To this, he adds the following further historical note:
In the eighth century Pope Hadrian I, according to Anastasius, suspended under the principal or triumphal arch, as it was called, a silver cross with 1365 or 1380 small lamps, which were lighted at Easter and other great festivals. This was perhaps the origin of the cross which used to be suspended in S. Peter's at this season.
Indeed, in period depictions showing old St. Peter's Basilica, this suspended cross is shown hanging above and just before the main altar.
While not used in precisely the same manner, one cannot but wonder if this cross is an ancestor of some sort -- or at least took its inspiration from -- that which hung in Old St. Peter's.
