Lecture 1: All Roads Lead to Rome
In this seminar, we will exam the different types of roads, the vehicles, the way stations, and traveler inns. The Romans had an extended road network stretching from northern England to North Africa, from the Iberic peninsula to modern-day Iran and Iraq, with a total length of no less than 120,000 km (74,565 miles) in the second century AD. Roman roads were made essentially to maintain control over the Empire’s vast territories allowing the rapid movement of armies wherever necessary.
Lecture 2: Technology of Water
This lecture will look at the innovative methods the ancient Romans used in regards to water. While the Romans did not invent the aqueducts—primitive canals for irrigation and water transport existed earlier in Egypt, Assyria and Babylon—nevertheless they introduced many innovations that allowed them to build aqueducts on an unprecedented scale. Hundreds of aqueducts eventually sprang up throughout the empire, some of which transported water as far as 60 miles. Perhaps most impressive of all, Roman aqueducts were so well built that some are still in use to this day. Rome’s famous Trevi Fountain, for instance, is supplied by a restored version of the Aqua Virgo, one of ancient Rome’s 11 aqueducts. Water was then distributed through a capillary net of pipes in fountains and baths. Only very few people could take advantage of tap water in their homes! The abundance of water also allowed the development of watermills where the power of the water hitting the wheels was often adjusted by a system of tanks and pipes. The Romans had other water devices used for sawing wood, stones, and for the crushing of metal ores. Sawmills had stone-cutting saws powered by waterwheels, using a crank and a connecting axle. Trip hammers, which used water wheels, cams, and hammers, were used in mining regions for crushing ore into small pieces.
Among the other extraordinary achievements of Roman engineers, there were bridges. The first stone bridges used stone blocks held together with iron clamps: by the mid-2nd century BCE, Romans made extensive use of concrete. Its use substantially increased the bridges' strength and durability. Bridges had arched structures that made them stronger and allowed for much longer bridge spans.
Lecture 3: Concrete, Arches, and Wall Facings–The “Roman Concrete Revolution”
This seminar will discuss one of ancient Rome’s greatest achievements: concrete. Many Roman structures like the Pantheon, the Colosseum, the Markets of Trajan are still standing today thanks to the development of Roman concrete. Its unique recipe, which used slaked lime and volcanic ash, is known as pozzolana and produced a sticky paste. Combined with volcanic rocks called tuff, this ancient cement formed concrete that could effectively endure chemical decay. Pozzolana helped Roman concrete set quickly even when submerged in seawater, enabling the construction of elaborate baths, piers, and harbors.
Arches have existed for roughly 4,000 years, but the ancient Romans were the first to effectively develop their power in the construction of bridges, monuments, and buildings. The ingenious design of the arch allowed the weight of buildings to be evenly distributed along with various supports, preventing massive Roman structures like the Colosseum from crumbling under their weight. Roman engineers improved on arches by flattening their shape to create what is known as a segmental arch and repeating them at various intervals to build stronger supports that could span large gaps when used in bridges and aqueducts. Along with columns, domes, and vaulted ceilings, the arch became one of the defining characteristics of the Roman architectural style. Besides the use of concrete, building techniques changed: ashlar blocks started to be replaced by regularly shaped cubilia, (little pieces of rock, cut in a pyramidal shape) and by bricks. Studying wall facings, it is possible to understand the evolution of Roman buildings as well as dating the structures quite precisely.
