Its spread was further helped by the entrepreneurial acumen of Hong's descendants. For example, when China began issuing stamps beginning in the Guangxu reign period (1875-1908), the Hong family quickly made their almanacs available by mail order. Also noteworthy is the fact that they produced a list of "recognized graduates of our training," confirming that certain students were certified as having learned their zeri skills from Jicheng Hall.
加以洪家幾代都有靈敏的商業頭腦，例如中國自清朝光緒年間開辦郵政，洪家很快就推出「郵寄擇日」；更特別的是在通書中列出各地「參校門人」名單，為這些列名的學生背書，保證他們的擇日術出自繼成堂一脈。