A wheelbarrow1 [is] formed of separable parts including:
(1) a bowl;
(2) a pair of elongate handles...;
(3) a bumper plate and [mounting] ...;
(4) a cross brace member having channel shaped sections on the opposite ends spaced from one another ... to receive the handle portions in fitting relationship within the channel sections...;
(5) a pair of leg members...;
(6) means for connecting the handles...;
(7) said cross brace member having a portion extending downwardly...;
(8) a wheel, and [mounting]...
- Radio Steel and Mfg Co. v. MTD Products, Inc., 221USPQ 657 (1984)
Aside from the ubi supra somewhat bone-dry legal defintion, the wheelbarrow is perhaps better described as an amazing invention most often used for carrying heavy goods around places of labour such as construction sites and venues of agriculture and horticulture. It is also occasionally used for transporting Chibuku, or even for human transport, although this is not advised as wheel-barrows are not designed for such a purpose.
What makes a wheelbarrow so brilliant is the fact that it only has one wheel. If a barrow uses two wheels then it becomes a hand cart which can cater for heavier loads, but which loses the intimacy of control, and thus the ability to manoevre it along steep and narrow planks, such as those often found on building sites. Likewise, a smaller two-wheeled barrow is the porters trolley, but the wheelbarrow has them all licked. No other one-man wheeled conveyance receptacle can be compared with a wheelbarrow for its overall functionality.
How It Works
The wheelbarrow consists of four main parts; the wheel, the bowl, the stands and the handles. The wheel is positioned at or near the front of the wheel barrow and together with the two stands, holds up the bucket in a sort of tripod arrangement when the wheelbarrow is at rest.
To put a wheelbarrow to its working purpose, you must place a burdensome object in the bowl section. The wheelbarrow then works essentially by combining the advantages of both the lever and the wheel. By the principle of moments, the further you are away from the load and the closer the load is to the axle, the easier it will be to lift. So, ensure the object is near to or over the axle. Then, perambulate to behind the wheelbarrow placing yourself between the handles and facing the wheelbarrow. Grasp one handle in each hand and lift the rear of the wheel barrow so that the stands are lifted off the ground and the wheel barrow rests only on its one wheel. You are now free to manoeuvre the wheelbarrow to the requisite destination. Emptying a wheelbarrow typically involves further lifting of the handles until the load slides out over the front wheel. A good builder's wheelbarrow will have a sort of tubular steel bumper-bar2 in front of the front wheel to provide stability that the wheel would not provide during out-tipping.
Wheelbarrow users should note that placing the load too far up towards the front end of the barrow such that the load is in front of the axle will make lifting the handles easier but controlling the wheelbarrow so much more difficult. Indeed, if the turning moment is sufficient to overcome the weight of the barrow itself, then the wheelbarrow may upend, spilling its load. Perhaps worse, if on an incline, it may be merely sufficient to reduce the friction between the stands and the ground and 'runaway' ... all the more reason to get a bumper-bar.
A Wheelbarrowful of History
"Ko Yu built a wooden goat and rode away into the mountains on it."
- Ancient (1st Century BC) Chinese Manuscript, apparently alluding to the construction and use of a wheelbarrow
The wheelbarrow has been around for donkey's years. Almost certainly first invented by the Chinese during the Han dynasty (206BC - 220AD), it is known to have been used extensively in both Chinese military campaigns and for agricultural purposes. The Chinese army recognised the tremendous advantage afforded to them in moving goods and, for some time, they are said to have kept their invention secret. Meanwhile, it is no coincidence that early Chinese agriculture is reckoned to have been some 30 times more efficient than its contemporary European counterpart3.
Chinese General Chuko Liang (181-234 AD) is generally credited as the inventor of the wheelbarrow, as it seems that a wheelbarrow was constructed under his jurisdiction, and is recorded in military specifications of the time. However, texts dating back to the 1st Century BC, make reference to one Ko Yu building a 'wooden goat'. If Ko Yu was the real inventor, then the secret was evidently well-kept for over 200 years.
Early prototype versions of the wheelbarrow had two wheels and were either push-along or pull-along, requiring two men for propulsion and steerage, and indeed, Ko Yu's 'wooden goat' may have been a two-wheeler, and would not (strictly therefore) have been a wheelbarrow. Constructed from wood, a pullable wheelbarrow (with handles at the front) was known as "a wooden ox", whilst the pushable option (i.e., with the handles at the back) was called "a gliding horse".
Liang's wheelbarrow was of the two-handled pushable sort, with one very large diameter single wheel set between a pair of coffin-like storage boxes. Subsequent Chinese were no slouches either, setting about converting the wheelbarrow into a kind of 'land-junk', by appending a mast and sail. Indeed, in 1974/75, Geoffrey Howard, a Parish priest from Manchester, England attempted to push a Chinese sailing wheelbarrow across the Sahara Desert, not entirely unsuccessfully.
Go West, Young Wheelbarrow
Italian explorer, Marco Polo is sometimes credited with having introduced the wheelbarrow to Europe when he returned to Venice from his Oriental adventures in 1295. However, whether or not Polo did in fact return bearing a wheelbarrow is perhaps irrelevant as there is some evidence that wheelbarrows were already in use in Gothic/Mediaeval Europe.
Perhaps most damning to the claims of those devotees of Marco Polo is a stained-glass window at Chartres Cathedral in North-West France, in which a wheelbarrow is depicted. Notably, the Cathedral was more or less completed in the early 13th Century, before Polo himself was even a twinkle in his father's eye.
Moreover, at around the same time, artist Matthew Paris was busy chalking up his work, 'Life of SS Alban and Amphibalus', in which a wheelbarrow also pops up.
From study of the work of Matthew Paris it is evident that the 21st Century western wheelbarrow has not changed much across almost a thousand years. Paris' barrow shows the wheel extended out of the front of the barrow, whereas the modern wheelbarrow's wheel is closer to the Chinese barrow in that the wheel is directly underneath at least some of the load.
However, one branch of wheelbarrow evolution has taken the form of the ballbarrow, created by the eponymous inventor of the cyclone vacuum cleaner, James Dyson. Like some bizarre sexual congress between a space-hopper and an industrial shovel, the ballbarrow has a giant orange ball in lieu of the wheel, which makes life easier on rough terrain and is better for wheeling across lawns as it spreads the weight more, thereby damaging the grass less. Likewise though, a good builder's or gardener's wheelbarrow will be equipped with a fairly wide-rimmed pneumatic tyre which more or less provides the same benefits, but without the suburban kitsch.
There are of course numerous other variations in terms of material of manufacture, shape and size. As already stated, the heavy-duty builder's barrow will be furnished with a bumper-bar and a pneumatic tyre. It is also likely to be made of steel. A concrete-mason's wheelbarrow is likely to be somewhat funnel-shaped at the front end to facilitate pouring of the slurry. Meanwhile a small-scale domestic gardener's wheelbarrow is perhaps lightweight aluminium, or even canvas, which can fold up for efficient storage. Perhaps more aesthetic than practical, examples of wooden wheelbarrows may still be spotted lurking in old potting sheds and tucked under the leylandii, home to gnomes, many of whom are equipped with their own miniature plastic or clay versions.
The Human Angle
Finally then, there is such a thing called the 'human wheelbarrow'. This is an entirely useless contraption as it carries nothing, and in fact, to boot, except perhaps among Chinese acrobatic circus troupes, does not require a wheel.
Despite being an uncommon activity among even consenting adults, human wheelbarrowing seems to be a common pastime among schoolchildren, who are particularly keen on 'wheelbarrow' races. However, conventional wisdom suggests that it appears inherently dangerous to the back, the neck, the clavicle and the arms, and it would not be surprising to find this activity prohibited in schools and discouraged at home. So don't do it, and don't let your children do it.
Thus said, to assemble a human wheelbarrow, a participating human should lie face down on the ground in the press-up position, but with legs apart. As with the real thing, you need to stand between the handles (the legs) facing the wheelbarrow (the rest of the body). With bent knees and straight back, grasp the ankles and lift. The person portraying the wheelbarrow should lift the weight of their upper body by flexing their elbows and straightening the arms, hands palm-down on the ground. You may now walk your 'wheelbarrow' by gently inducing forward motion, thereby forcing the 'wheelbarrow' to walk using their hands. Again however, the dangers to the spine and the neck are reiterated. Human wheelbarrowing is not a recommended activity.