《明史·志·卷四十九》
巡枧漕运，巡视关税，宣德四年设立钞关御史，至巫筮十年开始派遣主事。催运，监督烙马印，屯田。
在内两京刷卷，巡视京营，监临乡、会试及武举，巡视光禄，巡视仓场，巡视内库、皇城、五城，轮值登闻鼓。在外巡按，清军，提督学校，巡盐，茶马，巡漕，巡关，攒运，印马，屯田。
In the fourth year of Emperor Xuande's reign, inspectors were established to manage the transport of grain and the collection of customs duties, and from the tenth year of the Shu Bing reign onwards, these inspectors were sent to supervise cargo transportation, supervise the branding of horses, and manage military settlements.