OBELISCO DI PSAMMETICO II
594/589 BC,
erected for Psammetichus II at Heliopolis in Egypt
It was
transported to Rome by order of Augustus (27 BC/14) who placed it in 10 BC in a
square of about 160 x 75 m (525 x 246 feet) in the Campus Martius (north of
Parliament Square) as the sundial gnomon
It measures
22 meters (72 feet)
With base
and globe with papal coat of arms it measures 29 m (95 feet)
Augustus
took the advice of astronomers and mathematicians from Alexandria including
Facondo Novio
It was an
instrument for measuring time located on a square divided into a pattern of
bronze rules, but also a monument to the sun, to the stars and to the golden
Augustan aetas, the golden age of Augustus
It fell in
the ninth century and it was restored in 1792 with pieces from the Column of
Antoninus Pius (138/161) of red granite and moved in Piazza Montecitorio by
Giovanni Antinori (1734/92) at the behest of
Pius VI Braschi (1775/99)
The Column
of Antoninus Pius had been accidentally destroyed during the transport
organized by Francesco Fontana in 1705 from the nearby garden of monks in which
it had been found in Piazza Montecitorio
In 1998, a
renovation of the square by Franco Zagari (1945)
reinstated the visibility of the sundial
“The elegant
topography is reconstructed as it was before the change made by Ernesto Basile
at the beginning of the century, reconstructing a 'peacock's tail' similar to the
original by Carlo Fontana, the point of culmination of an upward momentum of no
less than four meters from the back of the piazza to the entrance of the
building (part of the 'monte'). This reintroduces a counter-movement to the
curvature of the palace by Bernini and Fontana, which is the essential key of
the Baroque conception of the square. The project makes visible the
sophisticated reuse of the obelisk as a sundial (...): a line on the ground
allows to read the 'true noon' (astronomical), when sunlight passes through a
hole of the spheroid on the top and makes a hole of light in the shadow on the
ground” (Franco Zagari Web Site - www.francozagari.it)
An
inscription on the base of the obelisk erroneously attributes it to Pharaoh
Sesostris
There are
two other Augustan inscriptions: the conquest of Egypt, and the dedication to
the sun
Every
September 23, the
birthday of Augustus, the shadow of the tip coincided with the entry of the Ara
Pacis
Every
April 21, the
birthday of Rome, one of the sides of the obelisk perfectly aligned with the
rising sun