The Wheelbarrow: Simple Machines that Changed Everything

Of all the simple tools humans have invented, perhaps none has combined simplicity and utility quite like the wheelbarrow. It is one of those objects that is so common in gardens and construction sites that most individuals don't even consider what the first wheelbarrow looked like. The wheelbarrow's origins are located about two thousand years ago and they are in China.

The oldest surviving picture of a wheelbarrow was drawn in China in the second century BC. A number of carvings made in 118 BC in Sichuan depict an Asian single-wheeled handcart with a figure pushing it on a construction site. There are also descriptions about the tool used in Asia during the first and second centuries AD, so it must have been in use before then.

Zhuge Liang (a Chinese military leader of the early third century AD) is often given credit for creating the wheelbarrow; historical sources attribute to him a "wooden ox" or "gliding horse," an invention described as a type of wheelbarrow that was used to carry military supplies and provisions.

Rather than placing the wheel on the front of the cart, as the modern European barrow has, the Chinese wheelbarrow typically had a much larger, central wheel. This puts the centre of gravity over the axle of the wheel, thereby supporting the weight directly. As a result, the operator was not responsible for carrying the load; the operator simply guided it.

In Europe, where the wheelbarrow did not emerge until the thirteenth century (over a thousand years after the earliest Chinese pictures and descriptions), there is not much doubt about the design of the tool, as there are many surviving depictions from the time. European versions were smaller and the wheel was placed on the front of the cart. While this would mean the operator had to bear much more of the load, it made the device easier to maneuver when space was confined (e.g., in mines and on building sites).

The exact route by which the device passed from East to West is unknown. Some historians have suggested that the technology may have been carried overland through trade, while others believe that the technology may have been a European re-invention. But regardless of how it was transmitted, the wheelbarrow had a profound impact on the human work load: it was used for millennia in construction, agriculture and mining; before the advent of machinery, there was simply no other way that humans could carry heavy loads, so a great deal of work fell on human shoulders.

Despite its long and unchanging history, the wheelbarrow is still in use in much the same way it was used by medieval Europeans.