Before 1925 the communications in Kwangsi and Kweichow, the two mountainous provinces, were difficult and brigandage was rife. As the fees charged on remittances were abnormally high under such circumstances, the merchants and other people going to and from those two provinces generally sent high-value postage stamps in lieu of remittance, thus affecting the remittance business of local Post Offices on the one hand and endangering mails on the other. The Directorate General of Posts at Peking consequently overprinted the characters 〝桂〞(Kuei) and〝黔〞(Ch'ien) in red ink on a batch of Hall of Classics stamps with N0.5 Sung characters, thus limiting their circulation to those two districts.