The radical polychromy of the Museum Building at Trinity College Dublin did not emerge Minerva-like from the brow of Benajmin Woodward, but rather from an imbrication of architecture, geology and engineering (fig. 2.1). While much is known about developments within these disciplines in the early Victorian period, relatively little is known of their relationship. How did geology and engineering come to influence architectural design and production? Why was it that structural columns of polished, polychrome, local limestone first appeared in architecture in Dublin in the 1850s? What was the impact in Ireland of this avant-garde polychromy? Louise Caulfield has shown the wealth of Ireland’s coloured limestone and its burgeoning exploitation in the period: this essay seeks to discover connective tissue between contemporary science, industry, politics and aesthetics.