**Anthemius of Tralles** was a

GreekThe Greeks, also known as the Hellenes , are a nation and ethnic group native to Greece, Cyprus and neighboring regions. They also form a significant diaspora, with Greek communities established around the world....

professor of

GeometryGeometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers ....

in

ConstantinopleConstantinople was the capital of the Roman, Eastern Roman, Byzantine, Latin, and Ottoman Empires. Throughout most of the Middle Ages, Constantinople was Europe's largest and wealthiest city.-Names:...

(present-day

IstanbulIstanbul , historically known as Byzantium and Constantinople , is the largest city of Turkey. Istanbul metropolitan province had 13.26 million people living in it as of December, 2010, which is 18% of Turkey's population and the 3rd largest metropolitan area in Europe after London and...

in Turkey) and

architectAn architect is a person trained in the planning, design and oversight of the construction of buildings. To practice architecture means to offer or render services in connection with the design and construction of a building, or group of buildings and the space within the site surrounding the...

, who collaborated with

Isidore of MiletusIsidore of Miletus was one of the two main Byzantine architects that Emperor Justinian I commissioned to design the church of Hagia Sophia in Constantinople from 532-537A.D.-Summary:...

to build the church of

Hagia SophiaHagia Sophia is a former Orthodox patriarchal basilica, later a mosque, and now a museum in Istanbul, Turkey...

by the order of

Justinian IJustinian I ; , ; 483– 13 or 14 November 565), commonly known as Justinian the Great, was Byzantine Emperor from 527 to 565. During his reign, Justinian sought to revive the Empire's greatness and reconquer the lost western half of the classical Roman Empire.One of the most important figures of...

. Anthemius came from an educated family, one of five sons of Stephanus of

TrallesAydın is a city in and the seat of Aydın Province in Turkey's Aegean Region. The city is located at the heart of the lower valley of Büyük Menderes River at a commanding position for the region extending from the uplands of the valley down to the seacoast...

, a physician. Of his brothers, Dioscorus followed his father's profession in Tralles; Alexander became at

RomeRome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...

one of the most celebrated medical men of his time; Olympius was deeply versed in

Roman jurisprudenceRoman law is the legal system of ancient Rome, and the legal developments which occurred before the 7th century AD — when the Roman–Byzantine state adopted Greek as the language of government. The development of Roman law comprises more than a thousand years of jurisprudence — from the Twelve...

; and Metrodorus was a distinguished grammarian in Constantinople.

As an architect he is best known for replacing the old church of

Hagia SophiaHagia Sophia is a former Orthodox patriarchal basilica, later a mosque, and now a museum in Istanbul, Turkey...

at

ConstantinopleConstantinople was the capital of the Roman, Eastern Roman, Byzantine, Latin, and Ottoman Empires. Throughout most of the Middle Ages, Constantinople was Europe's largest and wealthiest city.-Names:...

in 532; his daring plans for the church strikingly displayed at once his knowledge and his ignorance. His skills seem also to have extended to engineering for he repaired the flood defences at Daras.

Anthemius was also a capable mathematician. He described the string construction of the

ellipseIn geometry, an ellipse is a plane curve that results from the intersection of a cone by a plane in a way that produces a closed curve. Circles are special cases of ellipses, obtained when the cutting plane is orthogonal to the cone's axis...

and he wrote a book on

conic sectionIn mathematics, a conic section is a curve obtained by intersecting a cone with a plane. In analytic geometry, a conic may be defined as a plane algebraic curve of degree 2...

s, which was excellent preparation for designing the elaborate vaulting of Hagia Sophia. He compiled a survey of mirror configurations in his work on remarkable mechanical devices which was known to

Arab mathematiciansIn the history of mathematics, mathematics in medieval Islam, often termed Islamic mathematics or Arabic mathematics, covers the body of mathematics preserved and developed under the Islamic civilization between circa 622 and 1600...

such as Ibn al-Haytham.

A fragment of his treatise

*On burning-glasses* was published as

("Concerning wondrous machines") by L. Dupuy in 1777, and also appeared in 1786 in the forty-second volume of the

*Histoire de l'Academie des Instrumentistes*. A. Westermann gave a revised edition of it in his

(

*Scriptores rerum mirabilium Graeci*, "Greek marvel-writers") in 1839. In the course of the constructions for surfaces to reflect to one and the same point

- all rays in whatever direction passing through another point,
- a set of parallel rays,

Anthemius assumes a property of an ellipse not found in Apollonius work, that the equality of the angles subtended at a focus by two tangents drawn from a point, and having given the focus and a double ordinate he goes on to use the focus and directrix to obtain any number of points on a

parabolaIn mathematics, the parabola is a conic section, the intersection of a right circular conical surface and a plane parallel to a generating straight line of that surface...

—the first instance on record of the practical use of the directrix.

## External links