Friday, 2 April 2010

Canal Views 9

Lift Bridges

Movable bridges were usually cheaper to build than fixed bridges because they didn't require the same heavy foundations and structure.

These Lift bridges are counter-weighted and usually operated manually or by using a windlass like these are..

The bridge above was a bit different from most..... it as its own traffic light system... one press of a button and the lights change an d the traffic stops. Once through another press and the bridge lowers, the lights change to green and off gose the boat and any traffic on their way.

For this bridge the boats windlass came into play

A windlass is an apparatus for moving heavy weights. Typically, a windlass consists of a horizontal cylinder (barrel), which is rotated by the turn of a crank or belt. It was just a matter of a few turns before the counter balance comes into play and the bridge opened


SandyCarlson said...

Thanks for your explanations of how these things work, Tom. Your photos take me out of my world for a bit, and I appreciate that. You're great.

mrsnesbitt said...

Hmmm yes an explanation! I get many of these from hubby, most go over my head! lol!

This Is My Blog - fishing guy said...

Tom: Very cool shots.

EG Wow said...

I'd love to be there to watch the bridges go up and down. This is a fun journey.