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Boats using the S.C.C. paid by the mile traversed and the ton of cargo carried. In order to assess the weight of the cargo a system known as gauging was used.

Before its first trip on the S.C.C., the boat would be loaded with stone blocks of various known weights. At four points on the hull were markers, the distance between each marker and the water was measured. Then one of the blocks would be loaded into the boat, so that it settled lower into the water, and the distances measured again. More blocks were added and the measurements repeated. Thus a table was drawn up showing the relationship between the measurements and the weight of cargo for each boat.

After that, to determine the weight of cargo a boat was carrying it was only necessary to take four measurements and compare them with the table for that particular boat, which was held by the toll clerk.

Various tricks were employed by the boatmen to cheat the system. Having a heavy cabin stove fitted before gauging and then replacing it with a lighter one was one well-known trick. The canal company eventually decided to put a stop to this loss of revenue by means of a high-tech solution: they installed a boat-weighing machine at Midford. It resulted in an immediate substantial increase in the toll revenue, which showed how much money they had been losing with the gauging system (In actual fact, the weighing machine system was equally vulnerable to fraud, but most of the boatmen would not have understood how it worked and were not prepared to take the risk of being caught out trying to cheat it).


   The Aluminium Bridge   The Entrance Lock   The K&A Canal Bridge No.177   The Warehouse   The Toll House   Acraman's Crane   Gauging Blocks   Lock Keeper's Cottage   The Stop-plank Rack   More about the Somersetshire Coal Canal   >> Brassknocker Basin


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