Kevin T of NB Tranquility got it. It is the breather for the ground paddles on a lock on the Huddersfield Narrow Canal. The pepperpot-shaped device seems to serve as a bollard or strapping post too.
This is at Lock 12W.
Thoughts on a Narrowboat Part 2–Bow and Cratch - The longer I researched continuously cruising the more convinced I became the boat would need a sizeable storage capacity for fuel, potable water and sew...
1 day ago