Wheelbarrow

A wheelbarrow is a small hand-propelled vehicle, usually with just one wheel, designed to be pushed and guided by a single person using two handles at the rear, or by a sail to push the ancient wheelbarrow by wind. The term "wheelbarrow" is made of two words: "wheel" and "barrow." "Barrow" is a derivation of the Old English "bearwe" which was a device used for carrying loads.

The wheelbarrow is designed to distribute the weight of its load between the wheel and the operator so enabling the convenient carriage of heavier and bulkier loads than would be possible were the weight carried entirely by the operator. As such it is a second-class lever. Traditional Chinese wheelbarrows, however, had a central wheel supporting the whole load. Use of wheelbarrows is common in the construction industry and in gardening. Typical capacity is approximately 100 liters (4 cubic feet) of material.

A two-wheel type is more stable on level ground, while the almost universal one-wheel type has better maneuverability in small spaces, on planks or when tilted ground would throw the load off balance. The use of one wheel also permits greater control of the deposition of the load on emptying.

The earliest wheelbarrows with archaeological evidence in the form of a one-wheel cart come from 2nd century Han Dynasty Emperor Hui's tomb murals and brick tomb reliefs. The painted tomb mural of a man pushing a wheelbarrow was found in a tomb at Chengdu, Sichuan province, dated precisely to 118 CE. The stone carved relief of a man pushing a wheelbarrow was found in the tomb of Shen Fujun in Sichuan province, dated circa 150 CE. And then there is the story of the pious Dong Yuan pushing his father around in a single-wheel lu che barrow, depicted in a mural of the Wu Liang tomb-shrine of Shandong (dated to 147 CE). However, there are even earlier accounts than this that date back to the 1st century BCE and 1st century CE. The 5th century Book of Later Han stated that the wife of the once poor and youthful imperial censor Bao Xuan helped him push a lu che back to his village during their feeble wedding ceremony, around 30 BCE. Later, during the Red Eyebrows Rebellion (c. 20 CE) against Xin dynasty's Wang Mang (45 BCE–23 CE), the official Zhao Xi saved his wife from danger by disguising himself and pushing her along in his lu che barrow, past a group of brigand rebels who questioned him, and allowed him to pass after he convinced them that his wife was terribly ill.

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