This book has traced the figure of invisible architecture, in its combination of the hidden, the mobile and the transparent, across a range of nineteenth-century writers, cities and spatial forms. Throughout, I have attempted to show how apparently disparate features of urban space, and the drives that accompany them, gain new significance when read together as dimensions of this larger spatial complex. I have also sought to expand the ways we might think about architecture in relation to urban space and literature, moving beyond its most straightforward and obvious manifestations. Yet although I have proposed invisible architecture as a concept associated with modernity (which is itself, of course, not a stable or singular notion), it is not only applicable to the nineteenth century, nor to the cities and writers I have discussed. In this Conclusion I offer one example of how the ideas and approaches pursued in this book might be extended to another context, that of twentieth- and twenty-first-century New York. Applications to global and historical contexts at a greater remove from the texts I have discussed would also be possible, but New York since 1900 offers a combination of literary, cultural and architectural connections to, alongside divergences from, the concerns of this book that make it a fitting place to carry my readings one step further. I take as a starting point Christoph Lindner's claim that in New York, ‘the modern city does not disappear or perish in the era of globalization, but is subsumed and reconfigured’. If this is so, the question becomes: which features of invisible architecture are preserved or reconfigured in an increasingly globalised New York, and in what ways? In offering a provisional response to this question, this Conclusion begins to articulate how invisible architecture might continue to be of use beyond the primary framework in which I have developed it.

The examples that follow are necessarily highly selective. If New York is, as Kenneth Goldsmith's 2015 reimagining of the Arcades Project has it, the capital of the twentieth century, as Paris was of the nineteenth for Benjamin (and it has at least a reasonable claim to the title), then I cannot possibly do it justice here.

Gothic architecture has often been positioned as antithetical to urban modernity. In Contrasts: or, A Parallel between the Noble Edifices of the Fourteenth and Fifteenth Centuries and Similar Buildings of the Present Day; Shewing the Present Decay of Taste (1836), A. N. W. Pugin lays out the view that European Gothic was the pinnacle of Christian architecture and, in a related way, of unified social order, in contrast to the degraded and fragmented modern city. Before the English Reformation, it was ‘the faith, the zeal, and, above all, the unity, of our ancestors, that enabled them to conceive and raise those wonderful fabrics that still remain to excite our wonder and admiration’, but once ‘schism’ and ‘avarice’ took over, ‘the spell was broken, the Architecture itself fell with the religion to which it owed its birth, and was replaced by a mixed and base style’. For Pugin, the restoration of Gothic architecture must be accompanied by ‘a restoration of the ancient feelings and sentiments that motivated’ its creators, otherwise ‘all that is done will be a tame and heartless copy’. Similarly, at the end of Volume 1 of The Stones of Venice, which has celebrated Venetian Gothic, Ruskin argues that for city-dwellers, the function of architecture should be ‘to tell us about nature’, but that this is no longer possible in London, dominated by ‘grim railings and dark casements, and wasteful finery of shops, and feeble coxcombry of club-houses’. Ruskin contends that ‘the fresh winds and sunshine of the upland’ that true Gothic is able to evoke is always ‘better than the choke-damp of the vault, or the gas-light of the ball-room’, which define the modern city. As Barry Bergdoll observes, ‘the notion that Gothic was associated with England's glorious past and cherished institutions was established as early as 1741’, generating a form of Gothic nationalism that would later spread across much of Europe, alongside an attempt to ‘craft identity through nostalgia for a lost “natural” community’.

This chapter focuses on the structural role played by invisible architecture in Manchester, the ‘shock-city’ of the 1830s and 40s, in the writing of James Kay (1804–77; Kay-Shuttleworth from 1842), Friedrich Engels (1820–95) and Elizabeth Gaskell (1810–65). In different ways, these writers each position hidden, underground and unconscious spaces, in particular the cellar-dwelling, as both structurally necessary and disruptive to the industrial capitalist system which generates such spaces. This arrangement is the result of a spatial and social repression that seeks to preserve the existing form of capitalist relations of production, but in doing so throws up spaces whose invisibility to dominant forms of power provides an opportunity for emergent or residual forms of thought and praxis to subsist within the city, albeit in tenuous and marginal ways. As I will show, such invisibility is a risk. It provides limited opportunities for selfdefinition to some working-class characters in Mary Barton (1848), such as Alice Wilson, but leads to absolute degradation for others, such as the Davenport family.

I approach visibility and invisibility in these texts as two sides of what Henri Lefebvre calls the ‘double illusion’ by which space conceals its socially produced nature. This double illusion consists of ‘the illusion of transparency’ on one hand and ‘the illusion of opacity, or “realistic” illusion’ on the other. In the illusion of transparency, visibility is foremost and space appears to be an open realm of free activity, in the same way as free-market capitalism appears to allow individual freedom. In the realistic illusion, invisibility takes precedence, so that objects encountered in space function as material blocks of ideology, appearing to have a ‘natural’ reality that conceals their origins. In this second illusion, contingent structures are given a cloak of permanence, obviousness and self-sufficiency. In Mary Barton, we might think of the attitude taken towards a desperately hungry Jem Wilson by the Carson family's servants, who ‘would have willingly given him meat and bread in abundance; but they were like the rest of us, and not feeling hunger themselves, forgot it was possible another might’.

By naming his 1835 collection of essays and stories Arabesques, Gogol connected it to an aesthetic form at the intersection of architectural design and literature – not to mention music, art and dance – as well as a set of debates that had animated German Romanticism in the preceding decades. Taking Gogol's usage as inspiration, this chapter ranges across art, design, architecture, literature, philosophy and theory in order to argue for the value of the arabesque as a concept for reading the nineteenth-century city. In my readings, the arabesque functions partly as a metaphor which attracted increased attention in Europe and America at exactly the period modern cities were developing, and partly as a form with direct links to urban architecture and writing.

The arabesque's value as a conceptual framework for the modern city is due firstly to its persistent links with ‘movement and multiplicity’, as articulated in different ways by Kant, Goethe and Schlegel, and secondly to its position on the border between meaning, order and structure on the one hand, and meaninglessness, chaos and the unnatural on the other. At the risk of oversimplification, we might say that Western responses to the arabesque have tended to raise the question of whether it is purposive or non-purposive, and if purposive, whether this is in the Kantian sense of purposiveness which exists ‘apart from a purpose’. As Winfried Menninghaus observes, ‘without directly using the concept, Kant's Critique of Judgement (1790) formulates and elaborates a philosophy of the arabesque that then serves as a major touchstone for the reevaluation of the arabesque in early Romanticism’. Kant associates the arabesque with ‘free beauty’, which exemplifies purposiveness-without-a-purpose, when he writes that ‘designs à la grecque, foliage for framework or on wall-papers, etc., have no intrinsic meaning; they represent nothing – no object under a determinate concept – and are free beauties’. Free beauty does not conform to a particular purpose or structure, but instead activates the imagination (as opposed to pure or practical reason). It formally imitates nature, but does not reproduce it.

“A Portent, beyond Statues Sweating Blood in the Forum …” reconstructs the fire that destroyed San Paolo fuori le mura in July 1823 and the despairing responses the event provoked in Rome.

“Luigi Poletti and the Challenge of Rebuilding San Paolo” details how Poletti set about pursuing a completely revised project for San Paolo that was historicist in all but name and which aimed at salvaging what he perceived as the flawed Early Christian basilica building type by recasting it in a neo-Renaissance idiom.

“The End of a Generation” describes the moment in the early 1830s when several of the central protagonists in the story to this point died or retired from the scene, opening the way for Belli’s successor, the young Modenese engineer Luigi Poletti, to take over directorship of the project.