Proclaimed by Thomas Carlyle as the “Mechanical Age,” the nineteenth century saw a prevailing preoccupation with mechanical ingenuity and instrumental advancement in both the scientific and the literary worlds in Europe. This article examines a number of writings by Thomas De Quincey about human perception in the 1840s, exploring how they magnify the awkward and yet intimately entangled, symbiotic relationship between technology and poetry. In essays like “The Palimpsest of the Human Brain” (1845) and “System of the Heavens Revealed by Lord Rosse’s Telescopes” (1846), De Quincey embraces mechanical progress and its necessity in providing one with an unadulterated access to cosmic reality. However, in a later essay, “The Poetry of Pope” (1848), De Quincey would theorize the distinction between scientific and aesthetic writing, prioritizing poetic imagination over scientific facts. The article examines De Quincey’s epistemological dualism in relation to mechanical precision and explores how these essays disclose a more nuanced reading of scientific invention and its close alliance with the mediating and duplicating power of literary representation. It shows how De Quincey’s writing speaks to the Romantic longing for a convergence between empirical objectivity and spiritual transcendence by disquieting, or even dissolving, the mind-matter and human-machine dichotomies established in his cosmology. Furthermore, these essays utilize the notion of mechanical precision to make human perception accessible, manageable, and potentially reproducible, in order to claim a higher level of aesthetic potency.