 Although it continued to generate revenue from the sale of water , tolls produced only a small proportion of the canal 's income . In 1946 , against expenses of £ 12 @,@ 500 , it earned a total of £ 7 @,@ 296 , of which only £ 471 was from tolls . In 1951 total income was £ 8 @,@ 815 against a total expenditure of £ 9 @,@ 574 . In the same year , the canal carried 3 @,@ 933 long tons ( 3 @,@ 996 t ) of coal and no other materials . 
