It is not often that a piece of scholarship is able to achieve both delightful complexity and remarkable clarity, but Siobhan Carroll’s An Empire of Air and Water: Uncolonizable Space in the British Imagination, 1750–1850 helps set that standard.

The Introduction begins with a comparison of earlier cartographic practices to eighteenth- and nineteenth-century map-making; specifically, Carroll describes a shift from geographers loosely using rumours and assumptions to fill in uncharted areas to Jean-Baptiste Bourguignon d’Anville’s cartographic approach of leaving the ‘uncharted’ areas of Africa blank (p. 1). According to Carroll, this ‘blank’ on the map not only served as an imperial elimination of the settlements and cultures of those regions, but also marked them as colonisable in their emptiness. However, in that emptiness lay another level of significance for explorers: the empty spaces were not just ‘free’ for conquest, but the blankness also signified danger of the unknown (p. 5). From this illustration, Carroll’s conception of the ‘atopia’ emerges. Carroll defines atopias as natural regions which, despite seemingly being within the reach of scientific or colonial exploration, are intangible, inhospitable or inaccessible, and therefore reject incorporation into larger empires or settlements (p. 13). In An Empire of Air and Water, Carroll focuses on four atopic spaces: the poles, the ocean, the atmosphere and the subterranean. While the technologies of the eighteenth and nineteenth centuries opened further access into these regions, they were still primarily inhospitable, and travelling to, through and from these regions risked a high rate of mortality. Following the Introduction, An Empire of Air and Water is divided into four chapters, each devoted to one of Carroll’s atopias. Within each chapter, Carroll performs intensive analysis of primary texts, and while she does include some canonical works, she also includes archival artefacts and non-canonical titles to illustrate the wide application of her theory.

Carroll’s first chapter on ‘Polar Speculations’ discusses two important dimensions of polar space: first, while the poles appear ideal for imperialism (being unclaimed by any other nation), they cannot be permanently settled owing to nature’s erasure of colonial identifiers and the high mortality of explorers. Carroll illustrates the connection between explorations and literature, and how both genres informed not only each other, but also the cultural perception of the poles. Literature written before major polar explorations reinforced fantasies about the poles being gateways into other worlds or monstrous planes. At the same time, literature written during or after exploratory reports used descriptions of the icy other world to either push forward imperial claims or create boundaries and warnings against bringing the poles into the fold. Some of the major works addressed include Paltock’s Peter Wilkins, Coleridge’s The Rime of the Ancient Mariner, Shelley’s Frankenstein and Dickens’s The Frozen Deep.

Early in ‘Polar Speculations’, Carroll connects to her second chapter, ‘A Share of the Sea’. While the poles rest amid the ocean, neither atopia encourages settlement, and both seem in opposition to land which is both ‘claimable’ and physically bound (p. 20). Carroll describes the sea as a space of immense importance to the expansion of the British Empire. While the sea itself remained ‘unclaimable’, the ships on its waters were inexplicably connected to sovereignty (p. 78). Additionally, Carroll charts the language separation between maritime labourers and land-bound consumers. In this chapter, Carroll addresses a number of primary sources, including Falconer’s The Shipwreck, a children’s board game named The Bulwark of Britannia, Marryat’s The Naval Officer and Conrad’s Heart of Darkness.

In Chapter 3, ‘The Regions of the Air’, Carroll illustrates the stark difference in the path of conquest over the atmosphere compared with the oceanic and subterranean atopias. While the atmosphere held promises of imperial navigation without geographic boundaries and increased trade, the English were hesitant to invest in air travel—a space of mobility already claimed by French balloons. Therefore, literature from the time period presented the atmosphere as a space of vulnerability in the British Empire. Unlike the poles, ocean or subterranean regions, the air embodied ‘blankness’, and rejected most efforts at navigation and all efforts at permanent settlement (p. 120). The atmospheric atopia, then, predominantly developed in the imaginations of literature, including Inchbald’s The Mogul Tale, Chorley’s The Ballad of the Aeronaut, Shelley’s The Last Man and Wells’s War of the Worlds.

The subterranean underworlds in Chapter 4 are described as man-made ruins, wherein secret histories are uncovered, where Celtic faeries reside, where pockets of resistance disappear, or where cities of the undead lay fallen. Carroll, working from the etymology of ‘grotesque’ draws connections to the gothic and otherness, and shows how the subterranean also served as sanctuary outside the sovereign gaze (p. 149). Through her analysis of such texts as Defoe’s Robinson Crusoe, Sargent’s The Mine, Beckford’s Vathek, Lee’s The Recess, Byron’s The Island and Wells’s The Time Machine, Carroll addresses other topics including the erasure of labour, women explorers and the subterranean as an attribute of urban spaces.

An Empire of Air and Water’s conclusion, ‘“Dislocated Progress”: Atopias in Urban Space’, draws all four atopic spaces into London’s industrialised labyrinth. While the Romantics are characterised by a movement away from the urban and towards ‘the local’ (pp. 13 and 186), Carroll argues that Romantic literature also illustrates a similar move towards these half-imagined spaces, which remain untainted by colonial expansion. In Wordsworth’s The Prelude, DeQuincey’s Confessions of an English Opium-Eater and Reynolds’s Mysteries, London adopts elements of polar, oceanic, atmospheric and subterranean atopias. In these texts, Romantic authors create imagined maps of London, but these cartographic attempts only result in descriptions of London as an unmappable atopia, with London residents stranded as isolated, atopic explorers.

One can find little fault in this ambitious, interdisciplinary work, and Carroll’s approach to an accessible, well-organised Introduction followed by chapters of in-depth primary research and analysis should be a model for academic writing. Easily, An Empire of Air and Water is a text for scholars of Romantic and Victorian literature, environmental humanities, theorists of space and place (pp. 10 and 208), British colonialism, othering and travel writing, along with possible expansions into utopian studies, anthropology, urban and rural studies, gender studies and interests in material culture.