《梦溪笔谈·官政一》
食盐的运费，规定凡行一百里，陆运每斤收四钱，船运每斤收一钱，以此为准。
运盐之法，凡行百里，陆运斤四钱，船运斤一钱，以此为率。
The freight for edible salt is that every hundred li for land transportation, four qian shall be collected per catty, and one qian shall be collected per catty for water transportation, which shall be the benchmark.