Tuesday, June 15, 2004

Evidence of ancient complex machines in China

New Scientist: "Distinctive spiral patterns carved into a small jade ring show that China was using complex machines more than 2500 years ago, says a Harvard graduate student in physics.

The spiral-patterned ring is 27 millimetres in diameter and was probably a body ornament (Image: Science)
The ring was among the goods found in high-status graves from China's 'Spring and Autumn Period' from 771 to 475 BC. Most archaeological attention has focused on larger and more spectacular jade and bronze artifacts. But Peter Lu identified the patterns on the small rings as Archimedes' spirals, which he believes are the oldest evidence of compound machines.
Simple machines that move in only one way date back at least 5000 years, to the invention of the potter's wheel. But it took much longer to invent compound machines, which precisely convert motion from one kind into another.
Archimedes is sometimes credited with building an undescribed compound machine to move ships in the harbour of Syracuse in the third century BC, but the earliest well-accepted descriptions were by Hero of Alexandria in the first century AD."