Looking back at the lift. The side braces and pulley gear were added later |
But now we have. And a very enthralling experience it was too. Not thrilling; the descent is too smooth and gentle for that but fascinating to be using a system that dates back to 1875 when it was a prodigious feat of engineering.
Entering the caisson at the top of the lift |
To solve this time consuming process Edwin Clark was commissioned to design a lift to bring boats up and down between the two waterways.
His solution was elegantly simple. Two huge caissons – water filled tanks – were each supported on a single water filled ram and the rams joined by a pipe that allowed water to pass between them so they counterbalanced each other. Slightly increasing the water level in the upper caisson would increase its weight, moving it down while the other moved correspondingly upwards.
It all worked sublimely for a time, until the cast iron rams and the pistons began to suffer serious corrosion. In 1904 the whole lot was replaced by an electric motor powered system using pulleys, cables and massive counterweights to balance the caissons. These changes created the lift as it looks today – a new top deck carrying pulleys and motors was added above the original framework and large A-frame braces installed at the sides to take the load.
The descent begins inside the maze of girders and columns |
So what's it like? Each caisson takes two narrowboats and our companion boat, with an unpronouncable name, joined us to wait as the entry gate to the caisson was raised; we motored in and the gate closed behind. It looked a long way down. We were surrounded by a maze of massive diameter riveted cast iron columns and beams, built to the if-in-doubt-make-it-bigger philosophy of pre-computer age engineering.
As we go down the Anderton tripboat rises to meet us |
And carries on up towards the canal |
While we reach the river and the caisson door opens |
And then we were off onto the River Weaver where I swung a right and headed down river. But the Weaver is for tomorrow.
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