So how does a canal boat travel uphill?

Canal boats on the Grand Union Canal near Watford. Image: Roger Kidd/creative commons.

Sea-faring boats face many challenges, but uphills are not one of them. They have to deal with up-waves, of course, but that’s mostly easy because they just have to float and not flip over, which is a pretty low bar to set for a boat. Unique to canal boats is the need to drastically change elevation.

Coal-carrying boats, the original users of many of the UK’s canals, had to travel from the high coal-rich hinterlands down to the city and back again to keep the city dwellers warm and the factory fires burning. The altitude difference involved in doing so is pretty huge across the UK with the highest canal, Huddersfield Narrow at 654ft contiguously connected to waterways below sea level.

A canal is essentially a very long, very thin lake, meaning any incline will cause water to do its thing: flow downhill and flood the lower reaches. So, instead, different kinds of locks are used to lift boats from one level to the next.

While this works well when dealing with small inclines, locks can’t be too deep because each use would waste too much water. The alternative is what’s called a ‘lock flight’, which is essentially a staircase of locks that can be insanely time consuming to traverse. The Tardebigge Flight in Worcestershire, the longest in the UK, raises the waterway by 220 feet over the course of 30 locks. It takes an experienced crew a whopping four hours to navigate.

So boat lifts are the final piece in this weird puzzle. These are just what you imagine: a way of taking a boat, and the section of canal it’s on, from one level to the next. Lifts have the advantage of being far faster to use than lock flights, while also wasting much less water. Funnily enough the precursors to these feats of modern engineering far predate the relatively simple locks – the ancient Egyptians used crude lifts to get boats round waterfalls on the Nile.

 

The Falkirk Wheel connects the Forth and Clyde Canal with the Union Canal. Credit: Wikipedia/creative commons.

As is the case for most triumphs of engineering, Victorian Britain led the way. The Anderton Boat Lift in Cheshire has been taking water traffic the 50ft between the River Weaver and the Trent and Mersey Canal since its construction in 1875. Far grander boat lifts have since been built in other parts of the world, but little-Englander-waterway-enthusiast types can hang onto the fact the UK got there first. The most impressive modern example is the lift that gets ships over China’s Three Gorge Dam, which is simultaneously the highest and most powerful in world. Not nearly the same size but at least closer to home, the Falkirk Wheel in Scotland is incredible for looking like something out of Star Trek whilst still being a fully functional lift.

So that’s the briefest of outlines for all your boat-raising queries. If want to get more technical, try to wrap your head around the hydraulic systems beneath boat lifts such as Canada’s Peterborough Lift Lock. But if you really want a challenge try to square in your head how it can be that each lift weighs the same whether a boat is in it or not. It times like this I wish I had a bath; not for cleanliness’ sake but to conduct experiments with my rubber ducks. 


 

 
 
 
 

The Fire Brigades Union’s statement on Theresa May’s resignation is completely damning

Grenfell Tower. Image: Getty.

Just after 10 this morning, Theresa May announced that she would resign as Britain’s prime minister on 7 June. A mere half an hour later, a statement from Royal Institute of British Architects president Ben Derbyshire arrived in my inbox with a ping:

“The news that Theresa May will step down as Prime Minister leaves the country in limbo while the clock ticks down to the latest deadline of 31 October. While much is uncertain, one thing remains clear – a no deal is no option for architecture or the wider construction sector. Whoever becomes the next Prime Minister must focus on taking the country forward with policies beyond Brexit that tackle the major challenges facing the country such as the housing crisis and climate change emergency.”

I was a bit baffled by this – why would the architecture profession try to get its thoughts into a political story? But then Merlin Fulcher of Architects Journal put me right:

Well you know construction is a larger contributor to GDP than financial services, and most of the work UK architects do is for export, and at least half of the largest practice (Foster + Partners) are EU, so there's a lot at stake

— Merlin Fulcher (@merlinfulcher) May 24, 2019

So, the thoughts of the RIBA president are an entirely legitimate thing to send to any construction sector-adjacent journalists who might be writing about today’s big news, and frankly I felt a little silly.

Someone else who should be feeling more than a little silly, though, is Theresa May herself. When listing her government’s achievements, such as they were, she included, setting up “the independent public inquiry into the tragedy at Grenfell Tower” – a fire in a West London public housing block in June 2017 – “to search for the truth, so nothing like it can ever happen again, and so the people who lost their lives that night are never forgotten”.

Matt Wrack, general secretary of the Fire Brigades Union, is having precisely none of this. Here’s his statement:

“Many of the underlying issues at Grenfell were due to unsafe conditions that had been allowed to fester under Tory governments and a council for which Theresa May bears ultimate responsibility. The inquiry she launched has kicked scrutiny of corporate and government interests into the long-grass, denying families and survivors justice, while allowing business as usual to continue for the wealthy. For the outgoing Prime Minister to suggest that her awful response to Grenfell is a proud part of her legacy is, frankly, disgraceful.”

A total of 72 people died in the Grenfell fire. At time of writing, nobody has been prosecuted.

Jonn Elledge is editor of CityMetric and the assistant editor of the New Statesman. He is on Twitter as @jonnelledge and on Facebook as JonnElledgeWrites.

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