Ancient Life: Need a Lift?

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Five workers power a crane to hoist building materials to the roof of one of Rome’s monuments, in this relief from the first or second century A.D. The carving was found in the tomb of the Haterii family in Rome; Quintus Haterius Tychicus, a freedman, was probably a building contractor who helped erect some of the multi-storied, marble-clad buildings that lined the Via Sacra, the main street of the Roman Forum.

Passionate about machinery, the Romans used construction cranes like this one to build multi-level structures. The reason they could put up such large buildings was that they had invented an extremely strong and durable form of concrete (opus caementicium) in the early fourth century B.C. Roman concrete was made by mixing stone aggregate—pebbles or gravel—with a mortar of quicklime, water and sand. (Quicklime was produced by heating limestone until all the water in the stone evaporated.) The mixture was poured into special molds and allowed to harden.

The secret behind the strength of Roman concrete was its use of fine-grained volcanic sand from Pozzuoli, known as “pozzolana.” Pozzolana concrete was so durable that it was used to build the foundations of Roman bridges. Even river-borne sand and debris failed to erode the bridges’ concrete piers; some of these structures remain in use today.

Five workers power a crane to hoist building materials to the roof of one of Rome’s monuments, in this relief from the first or second century A.D. The carving was found in the tomb of the Haterii family in Rome; Quintus Haterius Tychicus, a freedman, was probably a building contractor who helped erect some of the multi-storied, marble-clad buildings that lined the Via Sacra, the main street of the Roman Forum. Passionate about machinery, the Romans used construction cranes like this one to build multi-level structures. The reason they could put up such large buildings was that they had […]