Mackay criss-crossed Taiwan from Miaoli north, and eastward to Ilan and Hualien. His journeys brought him into contact with Han Chinese speakers of both Hokkien and Hakka, as well as aborigines of both the plains and mountains.
馬偕的腳蹤遍及苗栗以北，東達宜蘭、花蓮，來往於閩、客、平埔、高山原住民之間。