Roman treadwheel crane
Grúa de rueda de pisar (polyspastos)
- Date
- c. 100 BCE · confidence low
- Place
- Rome, Italy
- Credited to
- Roman engineers; described by Vitruvius and in the relief of the Haterii
- Field
- Tools
What it is
A wooden derrick with a block and tackle and a treadwheel operated by men that lifts blocks of up to several tonnes with few workers. A construction tool of monumental Roman architecture.
Tong marks on Greek ashlar blocks of the 6th century BCE indicate simple cranes since the Archaic period.
What it led to
- Building tall structures with ashlar blocks of tens of tonnes (Baalbek, the Pantheon)
- A radical reduction in labour compared with the Egyptian ramps
- Medieval port and shipyard cranes directly derived from it
- Construction engineering as a technical profession
Built on
- Compound pulley (block and tackle)c. 250 BCE
- Capstan winch
- Treadwheel
- Greek crane (6th century BC)
Made possible
- Large-span concrete dome (Pantheon)c. 126 CE
- Medieval harbour crane
- Dome of the Pantheon
- Trajan's Column