This is the Barton Swing Aquaduct which carries the Bridgewater canal over the Manchester Ship canal. It was a direct replacement for the earlier stone built Barton Aquaduct.

When the ship canal was built the larger ships which used it could not fit under the original structure. The new aquaduct was designed by Sir Edwards Leader Williams. He was also involved in the Anderton Boat Lift another moving canal structure not too far away.

It became operational in August 1893 with the first commercial traffic using it in January 1894.

Clever people these Victorians.