Waterwheels are an incredibly versatile bit of kit! Growing up, I thought they were just a clever art installation adorning a wooded valley walk. However, as usual, I was wrong, so very wrong!
We’ve had wooden wheels, metal wheels, vertical, horizontal, overshot, breast and undershot wheels. Wheels for lifting water and rotating drive shafts for a whole host of machinery! Once in motion, the rotational energy could be transferred to gears and machinery, sometimes by leather belts or rods. We’ve had flat grinding stones, edge runners, trip hammers, ore-crushers, textile and paper mills all reliant on waterwheels!
Cast your minds back to 700 BC, this is when the ancient world saw its 1st non-human operated lifting device – the Egyptian Noria. The wheel was desperately needed to irrigate the dry lands for agriculture. It was a vertical wheel with clay pots and was turned by the current of the river – and undershot, if you will. The pots filled naturally at the bottom (dipped in the river) and as it got pushed round the upper buckets emptied into a well-placed trough or aqueduct.
Lovely! Water raised from river to purpose built infrastructure, where upon gravity took over.
Another use of the wheel was employed by the Persians in 250 BC to lift water out of the ground like a pump, but driven by animals on the surface – not water-powered – so doesn’t count!
The Romans didn’t do wheels by halves (as you can imagine). However, Vitruvius, an engineer of the Augustan age (31 BC – 14 AD) wrote about all things engineering, gave an account of the use of waterwheels, but basically said there was usually no point in using a waterwheel because of all the cheap slaves available!! Madness!!
Anyway, in Southern France in about the 4th century, they built a superb flour grinding complex on the side of a slope, consisting of 2 runs (side by side) of 8 waterwheels in series. It’s at Barbegal, Arles and was only discovered in 1940!
Ever heard of floating flour mills? Well, when Rome was under siege in 537 AD and the Goths cut off their water supply, they ingeniously took their mill operations onto the river. They made barges of floating mills with waterwheels operating between them. The piers anchoring the floating mills in place actually channelled and speed up the flow of water to the wheels – soon the whole of Europe was doing this apparently!
Meanwhile over in China, they were favouring horizontal style waterwheels. These, dipped in the edge of a flowing water course and span other wheels. Image definitely needed here! They also used the vertical wheel formation from around the 5th century AD, especially for their grinding ‘edge runners’ and trip hammers. Europe didn’t see these innovations for another 800 years!
Back to the UK and what do we know? Well, there seems to have been a medieval boom! Circa 900 AD there were thought to be less that 100 mills in England, but the Domesday Book, an English survey made in 1086 AD, lists 5,624 watermills! Boom!
There were boat mills, moored under the bridges of early medieval London and other cities in the 12th century; eventually to be replaced by structures joined to bridges. And there were tidal mills. Tidal mills were coastal dwellers and operated only when a head of water was caught by dam gates; they were opened as the tide came in and closed before it went out trapping sea water and channelling it through the mill race to the tidal mill. Most rivers sported a waterwheel to grind something or to spin blades for sawing wood!
Why the boom? It was because of the increase in grain production and the loss of cheap labour by plagues and wars. Agricultural methods were on the up and it had to be processed without people power.
The monks played a huge part – by the 12th century the Benedictine Monks were leaders in hydropower, metallurgy, beer and agriculture. They ran their enterprises around water power, using waterwheels to drive milling, wood-cutting, forging, and olive crushing machinery. It also provided running water for cooking, washing, bathing and sewage disposal! Tidy!
But then there was mining! In 1556 the book De Re Metallica, compiled by Georgius Argicola, shows us how they employed these beasts in early mining practices – underground as well as overground!
The mining industry needed the wheels for 3 reasons;
- to lift ore out of the ground and lower supplies down,
- to pump the water out,
- to crush the ore on the surface using stamps!
The main issue was the supply of water and unlike the grinding mills (or cotton mills as we shall shortly see) they had to be sited where the ore was, not where the water was. So elaborate leat systems were created (like the Mary Tavy Leat on Dartmoor) to deliver the water from the reservoirs to the overshot wheels located at the pit head.
There’s more though – the water wheels powered the cotton industry, not just the shipping and mechanisation! In 1771 Richard Arkwright opened a factory in Derbyshire powered by water, filled with his new spinning frames. This was the very first water-powered factory, but many others soon followed. They used increasingly larger wheels to turn gearing to drive an overhead belt system, delivering power to each machine from above. Less workers were required and in France the people smashed the machines in protest.
Also, the clever Cornish used the wheels in the clay industry to crush their clay into powders – like in the Tregargus Valley!
So, we have the parched Egyptians, the creative Chinese and the rampant Romans to thank for the early clever applications of the waterwheel, but then every practical profession from thereon for adapting and reinventing the technology to fit their circumstances – until steam hit the headlines in the 1700s that is!