McCausland's earliest publications advocate a form of premillennialism. His argument about Biblical prophecy requires the Bible to be a literal historical narrative, and he realised that this was called into question by the difference between the time-scale of Creation in Genesis and the age of the earth as revealed by geology. He therefore wrote Sermons in Stone, which advocates Hugh Miller's view that the "days" of Genesis were not twenty-four hour days but geological ages. McCausland published two works on ethnology, Adam and the Adamite (1872) followed by The builders of Babel (1874). In these works McCausland attempted to harmonise scripture with ethnology and argued that the Book of Genesis refers almost exclusively to only one race, the "Adamic", or Caucasian as opposed to multiple races. This was prompted by McCausland's realisation that prehistoric humans had lived before the period of Genesis; he argued that the Hebrew words Adam and Ish (both conventionally translatd as "Man" refer to two different human species. The "Adamite" or Caucasian/Indo-European was a special divine creation whose history was recorded in Genesis; all other races were supposedly incapable of higher thought or cultural development. The Chinese, he claimed, were descended from Cain; all human civilisations not directly traceable to European influence had been created by an extinct "Hamite" Adamite race (as outlined in his last book The Builders of Babel. Non-white races were doomed to disappear before the divinely-decreed expansion of the Adamites.
These two books on ethnology were influential to the Christian Identity movement and McCausland himself was an early proponent of Preadamism.
^Adam's ancestors: race, religion, and the politics of human origins, David N. Livingstone, JHU Press, 2008, p. 103.
^The forging of races: race and scripture in the Protestant Atlantic world 1600 - 2000, Colin Kidd, 2006, p. 162; Patrick Maume “Dominick McCausland and Adam’s Ancestors: an Irish Evangelical responds to the Scientific Challenge to Biblical Inerrancy” in Juliana Adelman and Eadaoin Agnew (eds) Science and Technology in Nineteenth-Century Ireland (Dublin: Four Courts Press, 2011).