Isidorius of Miletus

Sixth century a.d.

Turkish Architect and Engineer

Isidorius of Miletus was born in Turkey during the early sixth century. Along with Anthemios of Tralles, Isidorius designed and constructed the Church of the Holy Wisdom, or the Hagia Sophia, in Constantinople. This church, a magnificent example of Byzantine architecture and design, was built in 532-37 under the reign and personal direction of Emperor Justinian (483-565).

Little is known of Isidorius's early life. He was born in Miletus and presumably received his education and training in architecture and engineering in the city of Constantinople. In addition, he was a respected scholar and teacher, known for revising the work of Greek mathematician Archimedes (287?-212 b.c.) and writing a commentary of a book by Hero of Alexandria (first century a.d.), a mathematician who invented toys, a pneumatic pump, and a formula for expressing the area of a triangle. Isidorius invented a compass in order to study geometry and construct parabolas. Several of his students contributed to Elements of Geometry of Euclid and commentaries on the work of Archimedes.

Isidorius is best known for his architectural and engineering collaboration with Anthemios of Tralles in the design and construction of the Hagia Sophia. Justinian commissioned this masterpiece of Byzantine architecture after a fire destroyed the first church in 532. Justinian was the driving force behind the architectural revival that built or reconstructed more than 30 churches in Constantinople. Byzantine churches reflected a wide variety of styles. The Hagia Sophia, a basilica type, incorporated vaulted arches and domes and a very elaborate and ornate interior.

The Hagia Sophia is the crown jewel of Byzantine architecture. Isidorius and Anthemius, under the directives of Justinian, designed, engineered, and built one of the most memorable buildings in the history of architecture. A central dome rises 185 feet (56.4 m) to give the interior of the church a spaciousness that mimics the feeling of being outdoors. This illusion of space was achieved by the use of pendentives, a new building form designed and used for the first time in the construction of the Hagia Sophia. Four pendentives in the shape of curved or spherical triangles support the rim and are in turn locked into the corners of a square, formed by four huge arches. This engineering style based on the use of pendentives became known as "hanging architecture." It gave the interior of the buildings an open ethereal quality and was incorporated into the exterior of the building with immense buttress towers. Walls covered with colorful mosaics and elaborate designs conceal the outside of the church.

The Hagia Sophia was built in the remarkably short period of five years. The innovative nature of the design and perhaps the speed of construction made the structure unstable. The first dome fell after an earthquake, and its replacement needed to be repaired again in the ninth and fourteenth centuries. Nearly all churches built during the next 1,400 years reflected the architectural and engineering work of Isidorius of Miletus.

LESLIE HUTCHINSON