Copper miners in the Carpathian Mountains may have invented the wheel to facilitate the transportation of ore.
Archaeological evidence of wheels and wheeled vehicles appears extensively during the Bronze Age (around 5000 – 3000 BCE) across Europe, Asia, and North Africa, including battle scenes painted on walls, miniature wheels, children’s toys, burial carts, and even ancient texts. However, the rapid proliferation of the wheel has left scholars uncertain about its exact place and time of invention, or whether it was invented independently in different locations and periods.
The oldest known wooden wheel with an axle, dated to 5,200 years ago, was discovered in the Ljubljana Marshes, Slovenia, in 2002. (Photo: Imago).
In a study published in the journal Royal Society Open Science on October 23, historian Richard Bulliet, a professor at Columbia University, along with colleagues, presented how the wheel might have developed. Bulliet suggests that the wheel was invented in the Carpathian Mountains, Europe, around 4000 – 3500 BCE and subsequently spread in various directions.
Around 4000 BCE, copper ore became harder to find, requiring miners to venture deeper into mines and haul ore-laden carts out. The models of late Bronze Age carts found in the Carpathian region are rectangular with trapezoidal sides, similar to modern mining carts.
Using knowledge of ancient wheel systems based on archaeological evidence, the research team employed computational mechanics and design science to explore how ancient people transformed a simple rolling axle into a wheel and axle system. Due to the need to transport heavy baskets or barrels, ancient people may have placed rolling axles along a path, moving the rear axle to the front as needed.
The research team asserts that three improvements were necessary for the development of the wheel.
- The first improvement – a grooved axle – allowed barrels to sit on the rolling axle and move back and forth without requiring people to walk around to replace the axle. This enabled miners to push larger carts into the mine.
- The second improvement was a set of wheels fixed to the axle, allowing the cart to have a higher clearance to navigate stones and other obstacles in the mine.
- The third improvement, with wheels moving independently of the axle, may have appeared about 500 years later, enhancing maneuverability.
However, the research team notes that the wheel continued to evolve. For instance, the invention of the ball bearing in 1869 brought significant advancements to the automotive and machinery industries of the 20th century.
While helping to explain the invention of the wheel in Europe and its subsequent spread, the new study may not be the final word on the subject. “I think it’s still possible that many civilizations independently invented the wheel,” stated aerospace engineer Kai James at the Georgia Institute of Technology, a co-author of the new study.
