Bude Canal - The Inclined Planes

The Inclined Planes

The unusual feature of the canal was the six inclined planes. The tub boats had wheels, and on the inclined planes they were pulled up the slopes with the wheels running in channel rails (like a squat letter "U" in section). There were two sets of rails, one for each direction, but it does not appear that a counterbalancing system was used (in which a boat coming down would balance one being pulled up).

The tub boats were hauled up and let down the inclined planes by chains which were operated in most cases by waterwheels; the transit took five minutes or so. There were standby steam engines at some of the inclined planes. However the Hobbacott Inclined Plane used a different system of harnessing water power: water filled a very large bucket and it was simply the weight of the water that pulled the ascending tub boat up the incline. The bucket operated in a deep vertical shaft, and at the bottom a plug was opened and the water ran to waste along an adit which connected to the lower level of the canal; the descending bucket pulled an empty bucket up in the same operation. The full bucket had to be heavy enough to pull a loaded tub boat up the 1 in 4½ gradient as well as overcoming friction, and Green calculated that a weight of about fifteen tons was necessary. This was successful, and the bucket raised a boat up the plane in about four minutes, which was about one half of the time taken when the 16 horsepower (12 kW) standby steam engine was used.

The gradients of the planes differed somewhat, with Hobbacott being the steepest at 1 in 4½ and Vealand being the gentlest at 1 in 8.6.