During the Japanese occupation of Taiwan, popular almanacs were banned, but some were still smuggled in. When Taiwan was returned to Chinese rule, the Hongs immediately dispatched a specially hired boat to deliver 3000 tong shu to Taiwan.
日據時代通書被禁，仍有走私進來的；等到二次大戰一停，洪家立刻派請專船，將三千本通書送到台灣。