Uploader's Comments

Next time you walk along the canal and come upon Pasturefields Canal Bridge take a look at the wear on the walls and tow line grooves left on whats remains of the wooden line guard which protected the ropes from fraying against the brickwork as the horse drawn barges were pulled under the bridge.
Vertical wooden rollers or iron guard irons were fitted to bridges and lock furniture to stop such wear.
The guards often survive, as do the iron bearings for the wooden rollers, though most rollers have now disappeared