The origins of the modern Creationist movement in the USA can be traced to the publication of his first major work (with John C. Whitecombe), The Genesis Flood, in 1961. A hydraulic engineer by background, the book argued that any attempt to diminish the biblical account of a global flood does so at the expense of sound hermeneutics and biblical orthodoxy. It also sought to provide a working model of biblical ‘catastrophism’ rather than the uniformitarianism of geological changes usually adopted until then.