Comment by Dyac
10 days ago
There's also another unusual way - the Caisson lock.
Its design is TERRIFYING.
The boat is floated into a tube that get sealed at both ends and then (in the dark..) that tube is winched down into a completely flooded chamber until it (hopefully) lines up with the egress port at the bottom. The tube with the boat in is unsealed and the boat floats out.
Ooof, I'd never seen that. Thanks! From the wikipedia link:
> The May 1799 test at Oakengates carried a party of investors aboard the vessel, who nearly suffocated before they could be freed.
(!) ...and eventually they built a flight of nineteen locks instead, with a steam-powered pump to return water. The lift locks (and Falkirk Wheel) are a really impressive and elegant solution in comparison.
Oh that is terrifying; interesting, it "was first demonstrated at Oakengates on a now lost section of the Shropshire Canal in England in 1792". That little bit of rural UK was hot and happening from 1700 to 1800 and doing a lot of canal and river transport; it claims some part in the Industrial Revolution. Within 20 miles around Oakengates around that time was:
- early good quality cast iron; Abraham Darby in Coalbrookdale in ~1710 smelting iron from low-sulphur coal/coke for the first time, dominating the market in iron pots and pans.
- his foundry casting iron parts for early Newcomen steam engines in 1715 [2].
- the first iron bridge in the world[3] in 1781, now a town called Ironbridge. John Wilkinson invented a method of boring accurate cylinders for Bolton & Watt static steam engines, a friend wrote to him about the proposed iron bridge and he funded it.
- the first iron boat in 1787 in Brosely; the Trial by the same John Wilkinson, "convincing the unbelievers who were 999 in 1000".[7]
- the first iron framed building in the world, ancestor of skyscrapers. Thomas Telford[5] was a surveyor and engineer in the area, took inspiration from the iron bridge and started making other things out of iron, became friends with a flax mill owner whose mill burned down; they decided an iron framed building would be more fire resistant, and they built the first one ever[6] in 1797.
- very early high-pressure steam engine and high-pressure steam locomotive. Richard Trevithick around 1800; Coalbrookdale foundries built a static high pressure engine and a high pressure locomotive[4] within a couple of years of his Puffing-devil road locomotive and Pen-y-Darren rail locomotive were trialled in other parts of the UK.
Then Regression To The Mean happened and the area faded back into history.
[1] https://en.wikipedia.org/wiki/The_Iron_Bridge
[2] https://en.wikipedia.org/wiki/Newcomen_atmospheric_engine#Co...
[3] https://en.wikipedia.org/wiki/The_Iron_Bridge
[4] https://en.wikipedia.org/wiki/Richard_Trevithick#Puffing_Dev...
[5] https://en.wikipedia.org/wiki/Thomas_Telford
[6] https://en.wikipedia.org/wiki/Shrewsbury_Flaxmill_Maltings
[7] https://en.wikipedia.org/wiki/Vulcan_(barge)#Notes