210
The upper balcony is protected by an iron railing, in the middle of which is a
masonry pillar set on a GPS center. In alignment with the axis of the tower, a marble
plaque (40 × 40 cm) is affixed on the ground floor with a 4 cm diameter zinc center
and two orthogonal grooves in the center, engraved with the following inscription:
PUNTO GEODETICO FONDAMENTALE
MONTE MARIO
⊗
Origine
delle longitudini italiane
Today the tower can only be seen from the outside through a double fence that protects the military area in front of the fort.
The measure of the Central European Arc was also the reason for the construction
of the little tower above the tomb located just after Mile XI in Frattocchie, today
called Secchi’s tower.
12.4 Chronology of Geodetical Activities
In order to better understand the importance of the Via Appia Antica as a geodetic
site, it may be useful to outline the main events up to the present day:
• 1749–1750: Benedict XIV (1675–1758; Pope since 1740) orders the measurement
of the Rome-Rimini meridian.
• 1751: between April and May, Boscovich and Maire measure a geodetic baseline
along the Via Appia Antica for the calculation of the Rome-Rimini meridian arc.
• 1755: Maire designs the New Geographical Map of the Ecclesiastical State
(1:37500, 3 sheets), the first geodetically referenced map of the peninsula.
• 1809–1810: French engineers redo the measurements of Boscovich and Maire,
believing that they had identified the final endpoint in Frattocchie (Endpoint β),
and build a pillar there. Endpoint α (Cecilia Metella) is highlighted with a marble plaque.
• Around 1815: the French marker indicating Endpoint α is removed, leaving only
the two metal support spikes, still visible today.
• 1824: A. Conti and G. Ricchebach, astronomers of the Roman College, make
measurements using a baseline in Rome along today’s Via Ottaviano, Via
Barletta, and Viale Angelico to refute the French conclusions.
• 1836: G. Ricchebach builds the pillar with a little pyramid at the top between the
merlons of the Cecilia Metella mausoleum, on the south-west side.
• 1846: G. Ricchebach’s brother posthumously publishes the work Examination of
the triangulation of P. G. Ruggero Boscovich. Posthumous memory, Rome.
• 1850–1853: the archaeologist L. Canina performs the excavations of the Via
Appia Antica from Miles III to XI, bringing to light what is probably the base of
the French pillar at Frattocchie (Canina 1853).
T. Aebischer
The upper balcony is protected by an iron railing, in the middle of which is a
masonry pillar set on a GPS center. In alignment with the axis of the tower, a marble
plaque (40 × 40 cm) is affixed on the ground floor with a 4 cm diameter zinc center
and two orthogonal grooves in the center, engraved with the following inscription:
PUNTO GEODETICO FONDAMENTALE
MONTE MARIO
⊗
Origine
delle longitudini italiane
Today the tower can only be seen from the outside through a double fence that protects the military area in front of the fort.
The measure of the Central European Arc was also the reason for the construction
of the little tower above the tomb located just after Mile XI in Frattocchie, today
called Secchi’s tower.
12.4 Chronology of Geodetical Activities
In order to better understand the importance of the Via Appia Antica as a geodetic
site, it may be useful to outline the main events up to the present day:
• 1749–1750: Benedict XIV (1675–1758; Pope since 1740) orders the measurement
of the Rome-Rimini meridian.
• 1751: between April and May, Boscovich and Maire measure a geodetic baseline
along the Via Appia Antica for the calculation of the Rome-Rimini meridian arc.
• 1755: Maire designs the New Geographical Map of the Ecclesiastical State
(1:37500, 3 sheets), the first geodetically referenced map of the peninsula.
• 1809–1810: French engineers redo the measurements of Boscovich and Maire,
believing that they had identified the final endpoint in Frattocchie (Endpoint β),
and build a pillar there. Endpoint α (Cecilia Metella) is highlighted with a marble plaque.
• Around 1815: the French marker indicating Endpoint α is removed, leaving only
the two metal support spikes, still visible today.
• 1824: A. Conti and G. Ricchebach, astronomers of the Roman College, make
measurements using a baseline in Rome along today’s Via Ottaviano, Via
Barletta, and Viale Angelico to refute the French conclusions.
• 1836: G. Ricchebach builds the pillar with a little pyramid at the top between the
merlons of the Cecilia Metella mausoleum, on the south-west side.
• 1846: G. Ricchebach’s brother posthumously publishes the work Examination of
the triangulation of P. G. Ruggero Boscovich. Posthumous memory, Rome.
• 1850–1853: the archaeologist L. Canina performs the excavations of the Via
Appia Antica from Miles III to XI, bringing to light what is probably the base of
the French pillar at Frattocchie (Canina 1853).
T. Aebischer