The Solarium Augusti or Horologium Augusti (both

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

for "

Sundial A sundial is a horology, horological device that tells the time of day (referred to as civil time in modern usage) when direct sunlight shines by the position of the Sun, apparent position of the Sun in the sky. In the narrowest sense of the ...

of Augustus"; ) was a monument in the

Campus Martius The Campus Martius (Latin for 'Field of Mars'; Italian: ''Campo Marzio'') was a publicly owned area of ancient Rome about in extent. In the Middle Ages, it was the most populous area of Rome. The IV rione of Rome, Campo Marzio, which covers ...

ancient Rome In modern historiography, ancient Rome is the Roman people, Roman civilisation from the founding of Rome, founding of the Italian city of Rome in the 8th century BC to the Fall of the Western Roman Empire, collapse of the Western Roman Em ...

constructed in 10 BCE under the

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emperor The word ''emperor'' (from , via ) can mean the male ruler of an empire. ''Empress'', the female equivalent, may indicate an emperor's wife (empress consort), mother/grandmother (empress dowager/grand empress dowager), or a woman who rules ...

Augustus Gaius Julius Caesar Augustus (born Gaius Octavius; 23 September 63 BC – 19 August AD 14), also known as Octavian (), was the founder of the Roman Empire, who reigned as the first Roman emperor from 27 BC until his death in A ...

. It included an

Egyptian ''Egyptian'' describes something of, from, or related to Egypt. Egyptian or Egyptians may refer to: Nations and ethnic groups * Egyptians, a national group in North Africa ** Egyptian culture, a complex and stable culture with thousands of year ...

obelisk An obelisk (; , diminutive of (') ' spit, nail, pointed pillar') is a tall, slender, tapered monument with four sides and a pyramidal or pyramidion top. Originally constructed by Ancient Egyptians and called ''tekhenu'', the Greeks used th ...

that had first been erected under the

pharaoh Pharaoh (, ; Egyptian language, Egyptian: ''wikt:pr ꜥꜣ, pr ꜥꜣ''; Meroitic language, Meroitic: 𐦲𐦤𐦧, ; Biblical Hebrew: ''Parʿō'') was the title of the monarch of ancient Egypt from the First Dynasty of Egypt, First Dynasty ( ...

Psamtik II used in some fashion as a

gnomon A gnomon (; ) is the part of a sundial that casts a shadow. The term is used for a variety of purposes in mathematics and other fields, typically to measure directions, position, or time. History A painted stick dating from 2300 BC that was ...

. Once believed to have been a massive

sundial A sundial is a horology, horological device that tells the time of day (referred to as civil time in modern usage) when direct sunlight shines by the position of the Sun, apparent position of the Sun in the sky. In the narrowest sense of the ...

, it is now more commonly understood to have been used with a meridian line used to track the solar year. It served as a monument of Augustus having brought Egypt under Roman rule and was also connected with the Altar of Augustan Peace commemorating the

Pax Romana The (Latin for ) is a roughly 200-year-long period of Roman history that is identified as a golden age of increased and sustained Roman imperialism, relative peace and order, prosperous stability, hegemonic power, and regional expansion, a ...

established by his ending the numerous civil wars that ended the

Roman Republic The Roman Republic ( ) was the era of Ancient Rome, classical Roman civilisation beginning with Overthrow of the Roman monarchy, the overthrow of the Roman Kingdom (traditionally dated to 509 BC) and ending in 27 BC with the establis ...

. The Solarium was destroyed at some point during the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similarly to the post-classical period of global history. It began with the fall of the Western Roman Empire and ...

. Its recovered obelisk is now known as the

Obelisk of Montecitorio The Obelisk of Montecitorio (), also known as Solare, is an ancient Egyptian, red granite obelisk of Psamtik II (595–589 BC) from Heliopolis. Brought to Rome with the Flaminio Obelisk in 10 BC by the Roman Emperor Augustus to be used as the ...

History

It was erected by the emperor

, with the 30-meter Egyptian red granite

, that he had brought from Heliopolis in ancient Egypt. The obelisk was employed as a

that cast its shadow on a marble pavement inlaid with a gilded bronze network of lines, by which it was possible to read the time of day according to the season of the year. The ''solarium'' was dedicated to the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

in 10 BCE, 35 years after Julius Caesar's calendar reform. It was the first solar dedication in Rome. The Solarium Augusti was integrated with the

Ara Pacis The (Latin, "Altar of Augustan Peace"; commonly shortened to ) is an altar in Rome dedicated to the Pax Romana. The monument was commissioned by the Roman Senate on July 4, 13 BC to honour the return of Augustus to Rome after three years in Hisp ...

in the Campus Martius, aligning with

Via Flaminia The Via Flaminia () was an ancient Roman roads, Roman road leading from Rome over the Apennine Mountains to ''Ariminum'' (Rimini) on the coast of the Adriatic Sea, and due to the ruggedness of the mountains was the major option the Romans had f ...

, in such a way that the shadow of the gnomon fell across the center of the marble altar on 23 September, the birthday of Augustus himself. The obelisk itself was set up to memorialize Augustus' subordination of Egypt to the control of the Roman empire. The two monuments must have been planned together, in relation to the pre-existing

Mausoleum of Augustus The Mausoleum of Augustus (; ) is a large tomb built by the Roman Emperor Augustus in 28 BC on the Campus Martius in Rome, Italy. The mausoleum is located on the Piazza Augusto Imperatore, near the corner with Via di Ripetta as it runs along th ...

, to demonstrate that Augustus was "born to bring peace", that peace was his

destiny Destiny, sometimes also called fate (), is a predetermined course of events. It may be conceived as a predetermined future, whether in general or of an individual. Fate Although often used interchangeably, the words ''fate'' and ''destiny'' ...

. According to the ''Cambridge Ancient History'', "the collective message dramatically linked peace with military authority and imperial expansion." In his ''

Natural History Natural history is a domain of inquiry involving organisms, including animals, fungi, and plants, in their natural environment, leaning more towards observational than experimental methods of study. A person who studies natural history is cal ...

'', Pliny remarks that in the monument had stopped accurately reflecting the solar year by about 40 CE and offers several explanations for the shift, including that the sun, the earth, or both might not be as fixed in their position and movement as was usually believed at the time. The obelisk was illustrated, supported by a reclining figure, on the base of the

Column of Antoninus Pius The Column of Antoninus Pius () is a Roman honorific column in Rome, Italy, devoted in AD 161 to the Roman emperor Antoninus Pius, in the Campus Martius, on the edge of the hill now known as Monte Citorio, and set up by his successors, the ...

. The obelisk gnomon was still standing in the 8th century CE, but was thrown down and broken, then covered in sediment; it was rediscovered in 1512, but not excavated. In a triumphant rededication, the ' Montecitorio obelisk' was re-erected in Piazza di Montecitorio by

Pius VI Pope Pius VI (; born Count Angelo Onofrio Melchiorre Natale Giovanni Antonio called Giovanni Angelo or Giannangelo Braschi, 25 December 171729 August 1799) was head of the Catholic Church and ruler of the Papal States from 15 February 1775 to hi ...

in 1789.

Archaeology

Edmund Buchner excavated some sections of the calibrated marble pavement of the Solarium Augusti under the block of houses between

Piazza del Parlamento Palazzo Montecitorio () is a palace in Rome and the seat of the Chamber of Deputies (Italy), Chamber of Deputies, the lower house of the Italian Parliament. History The palace's name derives from the slight hill on which it is built, which wa ...

and Piazza San Lorenzo in Lucina. Recent studies have challenged Buchner's reconstruction of the Solarium as a full sundial, maintaining that the archaeological and textual evidence indicates a simple meridian line, marking the changing noontime position of the Sun in the course of the year.Peter Heslin, "Augustus, Domitian and the So-Called Horologium Augusti", ''The Journal of Roman Studies'', 97 (2007: 1-20).

Notes

References

*The broad context of the Augustan iconographic program, of which the Solarium Augusti is part, is presented in ''The Power of Images in the Age of Augustus'' by Paul Zanker; University of Michigan Press; 1988.

External links

Paul Zanker, "The Augustan Program of Cultural Renewal (part two)
The Solarium Augusti in the context of Augustan monuments.

* ttp://www.unicaen.fr/rome/visite3.php?action=biblio&langue=anglais&id=horologium&idMonu=17 "The Horologium of Augustus: a bibliography"br>''Horologium of Augustus'', part of the Encyclopædia Romana
by James Grout
Meridian vs. Horologium-Solarium
{{Authority control Sundials Ancient Roman buildings and structures in Rome Buildings and structures completed in the 1st century BC Rome R. IV Campo Marzio Campus Martius

History

Archaeology

See also

Notes

References

External links