Got there often on foot Sharon. The nautical expedition had to be abandoned as the towpath party sighted a band of hostiles approaching at speed from the direction of Blackhill, a precipatate undignified flight eastwards was the outcome, leaving the hostiles in posession of said raft.
The canal split, one branch went north to the locks and the other, a dead end, went to the Gazoon where barges used to be lowered down an "inclined plane" to the basin. This apparently saved time & water. It must have been a later improvement to the canal and the only one in Scotland?
Here's an English example.
http://www.fipt.org.uk/lift.html Also known as the Valley there were a couple of canal houses there, one at the bottom and one at the top, presumably for the operators and their families. The barges were hauled onto a caisson which I take it is English for Gazoon. The full one descending hauled up another with the empty barge. It was long gone when I knew it, just leaving the name and the earthworks, sadly no trace now remains.
Ah hesitate to suggest that it's "aw under the motorway noo", in case somebody comes doon on me like a ton of bricks.