LocksA lock is a device used for raising and lowering boats, ships and other watercraft between stretches of water of different levels on river and

canal waterways. The distinguishing feature of a lock is a fixed chamber in which the water level can be varied; whereas in a caisson lock, a boat lift,

or on a canal inclined plane, it is the chamber itself that rises and falls.

C/W Monday 18th May 2015

Aqueducts

• Bridges for conveying water, called aqueducts or water bridges are constructed to convey watercourses across gaps such as valleys or ravines.

Tunnel

• A canal tunnel is a tunnel for a shipping canal. The longest canal tunnel in the world is the Rove Tunnel in France, presently disused. The proposed Stad Ship Tunnel in Norway, while shorter, will be significantly wider and deeper, as it is designed to accommodate seagoing vessels.

Legging

• Early canal tunnels were built without a towpath as this would require a much larger bore, and hence cost more to build. Prior to the introduction of motorized boats, legging was one of the few options for getting a boat through such a tunnel.

• By amir c