《明史·志·卷五十六》
河盐，是不存入仓库，在河边直接提前支取，容易支取而获利快捷。
河盐者，不上廪囷，在河径自超掣，易支而获利捷。
River salt was salt that was not stored in warehouses; it was collected directly at the river, so it was easy to obtain and one could profit quickly.