History What it was
Roman builders lifted huge stone blocks, columns and beams without engines. They used wooden cranes with ropes and pulleys. For the heaviest loads, the crane was powered by a large wooden wheel. Workers walked inside the wheel like a hamster in a wheel, turning it and winding up the rope.
History How it worked
Pulleys make lifting easier. By running a rope through several wheels, a small pulling force can lift a much heavier load, though the rope has to be pulled further. A big treadwheel added even more power, because the wide wheel turned a narrow drum that wound the rope.
The Roman architect Vitruvius described several lifting machines in his book On Architecture, including cranes with many pulleys and one turned by men walking inside a drum-wheel.
History Evidence
A carved stone relief from the Tomb of the Haterii, a family tomb near Rome, shows a large crane with a treadwheel being used to build a monument. It is now in the Vatican Museums. Modern engineers have built working copies of Roman treadwheel cranes to test how they lifted stone.
Art In this artwork
This crane is an artistic illustration. The soft glow around it is part of the original artwork.
Look closer
- Follow the rope from the wheel to the stone block.
- Find the pulleys at the top of the arm.
Think about it
- How does a big wheel make a heavy stone easier to lift?
- What machines do builders use today instead?
- What would it be like to work inside the wheel?
Key words
- Pulley
- A wheel with a rope that helps lift loads.
- Treadwheel
- A wheel turned by people or animals walking inside it.
- Relief
- A carving that stands out from a flat surface.
Use it in class
- Roman engineering: arches, concrete, roads and domes (Lesson, grades 6-10)
Sources
The history on this page is a short summary based on these sources:
- Vitruvius, On Architecture (1st century BC), Books 2, 5, 8 and 10
- Smarthistory, "Roman funeral rituals and social status: the Amiternum tomb and the Tomb of the Haterii"
