Haghia Sophia - Strolling Through Istanbul: The Classic Guide to the City - page 47

Fossatis at the time of their restorations in 1847-9.) These have never
been covered; we see them in pictures of Haghia Sophia across the
centuries, hovering eerily over the nave. Evliya Çelebi believed them to
be talismans, albeit moribund ones, as he tells us in his Seyahatname :
“Before the birth of the Prophet these four angels used to speak, and
gave notice of all the dangers which threatened the Empire and the
city of Istanbul; but since his highness appeared all talismans have
ceased to act.” Their faces are sometimes exposed, sometimes covered,
most recently by the Fossatis' gold-starred medallions, which are still
in place. Unfortunately, these mosaics have not yet been cleaned and
restored and are a bit dirty and discoloured. It is not certain whether
these heavenly creatures are intended to be seraphim or cherubim;
the former are said by Isaiah to have, like these, six wings: “With
twain he covered his face, and with twain he covered his feet, and
with twain he did fly,” while Ezekiel informs us that cherubim had
only four (or eight) wings. But as Cyril Mango amusingly shows,
Byzantine artists do not seem to have understood or observed the
distinction between the two Orders; he suggests that perhaps we
have here one of each. As to date, Mr. Mango points out that since
both pendentives were largely destroyed in the collapse of 1346, the
mosaics must be subsequent to that time; they doubtless belong to
the period of restoration after the collapse, between 1346 and 1355.
But they certainly replace, and may closely copy, older mosaics of the
same subject.
THE GALLERIES
All of the remaining mosaics are in the galleries and in the rooms
adjacent to them. The public entryway to the galleries is at the
northern end of the narthex, where an inclined labyrinth leads us to
the angle of the western and northern galleries. Before we examine
the mosaics we might walk to the central or western gallery, from
whence we can orient ourselves and enjoy a splendid view of the nave.
Just next to the balustrade at the centre of this gallery we see the
spot where the throne of the Empress was located; it is marked by a
disc of green Thessalian marble set into the pavement and framed by
a pair of coupled columns in green marble. Although Procopius