Physics

In Byzantium physics was not an independent branch of science, as it is today, but belonged to the sciences of mathematics and mechanics. Later, in Middle and Late Byzantium, physics supplemented other subjects, such as arithmetic, geometry, music and astronomy. Typical cases of scientists who dealt with physics are the two architects of Agia Sophia, Anthemius of Tralles and Isidore of Miletus. Anthemius came from a family of scholars. Born in Alexandria, he was educated under the philosopher, astronomer and orator Ammonius.

Several authors refer to his particular bent for mathematics and engineering, as well as to his scientific work in both fields. More specifically, in mathematics he developed the theory of ellipses and co-wrote On the Parabola, a work analyzing how parabolas are made; his contribution to developing the theory of conic sections is also regarded as significant.

In the field of engineering he set out his theory of concave mirrors in On Wondrous Machines, where he explains how solar rays can be concentrated in one spot with the aid of a concave mirror, regardless of season and time. There is an anecdote about Anthemius that shows how capable he was at finding dynamic solutions: his neighbour, Zeno the orator, added an upper floor to his house, thus blocking off the light to Anthemius’ one storey home. To get his revenge Antemius built a boiler and pipe mechanism which, when heated to boiling point, produced an artificial steam-induced earthquake, an explosion and damage to the neighbour's extension.

Isidore, the other Agia Sophia architect, had a broad education. He was as good a mathematician as Anthemius, and saw to the publication of Aristotle’s works. One of his students - possibly the engineer and astronomer Leontes - rescued the fifteenth book of Euclid. Furthermore, the interest Anthemius took in engineering is evident from his preoccupation with Geodesica, a lost work by Hero on the construction of domes.
 
Mechanical Engineering
Inventions in engineering were not disseminated in Late Antiquity; they arose as the result of ordinary artisans or slaves improvising in local workshops. This meant that any idea was left without being further developed, improved or put into mass production.

One exception was Pappus, a Greek mathematician, geometer and engineer who lived in Alexandria in the 3rd-4th century. In his work Synagoge (or Collection) he gathered together all the devices thus far considered landmarks in the history of engineering: levers, catapults, water hoisting machinery, "automatons" (automatic devices), solar and hydraulic clocks and globes with celestial bodies that were activated by hydraulics.

Particularly in the case of automatons, anyone interested in devices operated by hydraulic fluid systems (water or air) consulted the work of Hero of Alexandria. One such device with hydraulic and mechanical moving parts was the three-story clock of Gaza, as described by the orator Procopius in the early years of the 6th century: a mechanical trumpet call every hour was accompanied by movement of a statue of Helios (the sun god) to point at one of twelve doors in the upper floor, which opened to reveal a sculpture ensemble depicting one of the twelve labours of Hercules. The royal throne in the palace of Magnaura was equipped with similar systems too. According to the descriptions by both Emperor Constantine Porphyrogenitus and Liutprand, later Bishop of Cremona, the throne rose up to the top of the formal hall, while at the same time instruments played music, metal lions opened their mouths and roared, and birds sang on silver trees above the throne. Thus up until the 7th century knowledge of engineering was possessed by scholars in the capital and the provinces, and they passed on major mechanical accomplishments of their own time or earlier to the wider public. From the 9th century onwards, however, engineers worked exclusively for the emperor and the palace, as is testified by the elaborate mechanism at the Byzantine emperor’s throne.

Geometers knew how to use a surveying instrument called the dioptra. A seventh or eighth century topographer known to us as Hero co-wrote a book on how to solve practical problems involved in calculating distances between points and surfaces using the dioptra, which is considered the precursor of today's theodolite. The astrolabe was the chief instrument of astronomy, used to calculate the azimuth and determine the distances between celestial bodies. Important Byzantine scholars such as John Philoponus, Nicephorus Gregoras and Isaac Argyros wrote on the astrolabe and its use. The only surviving Byzantine astrolabe, with an inscription dating it to 1062, is held in the Museum of Brescia.