Failed ventures are quickly forgotten, pushed to the back of collective consciousness, where they run little risk of dampening enthusiasm for future projects’ promising success. When John Dryden's play The Indian Emperour was first performed in 1665, audiences were transported back in time to contemplate Spanish explorers in the Americas marvelling at the gold that had evidently been placed there by God for the exclusive benefit of intrepid Europeans. One conquistador remarks to his companion, a fictionalized version of Hernán Cortés, ‘Methinks, we walk in dreams on fairy Land’ – a line that seems designed to encourage English spectators indulging in their own gilded imaginings of the abundant riches awaiting them in Africa. Silk-obsessed visionaries with selective memories glossed over both the collapse of Cortés's ambitious attempts to cultivate silkworms in Spanish America and the more recent English proposal to cut out Asian suppliers by creating a profitable home-grown silk industry (it petered out under the double burden of trying to grow the wrong sort of mulberry tree in the wrong sort of weather). Instead, England was spinning silken dreams for Virginia – but they also evaporated under the harsh light of reality.

In Unravelled Dreams: Silk and the Atlantic World, 1500–1840, Ben Marsh skilfully converts entrepreneurial losses into scholarly gains, providing a much-needed counterbalance to triumphalist tales of innovative success and unsettling easy assumptions of inevitable technological progress. Hopeful Europeans repeatedly launched sericultural initiatives, but for various reasons they all eventually faded into oblivion. Yet their effects were significant and wide-ranging: while they flourished, they brought profits to investors, employment to labourers and lasting legacies to the Americas. Connecting these diverse schemes together, Marsh investigates three main aspects of Atlantic imperialism: apparently unquenchable confidence in the potential for European achievement; the limitations imposed by environmental conditions; and the major but often concealed importance of marginalized peoples from different cultural backgrounds, including large numbers of women.

This excellent book relies on meticulous research spanning an unusually wide range of times, places and cultures. It opens in 1503, when the first transatlantic silkworm passengers died on their enforced voyage from Granada, and it closes metaphorically in 1837, the year when Hans Christian Anderson published ‘The emperor's new clothes’, which Marsh presents as an appropriate morality tale for American manufacturers who were obstinately proclaiming the health of the national silk-producing industry while it disintegrated around them.

Organized chronologically, Marsh's analysis proceeds in three sections of roughly equal length. The first, ‘Emergence’, describes early initiatives to introduce mulberry trees and silkworms into the Americas, focusing on New Spain, Virginia and French possessions round the Caribbean. Next comes ‘Persistence’, a discussion first of various endeavours to produce silk in Europe, and then of Britain's ambitions in its North American colonies. Finally, ‘Convergence’ describes how diverse American concerns were integrated into a single programme during the last third of the eighteenth century. As an epilogue, Marsh considers the post-Revolutionary bid to create a nationwide industry: as he puts it, ‘making American silk now depended upon making silk American’ (p. 9). Although some committed sericulturalists struggled on, by the middle of the nineteenth century the silk bubble had exploded.

Beautifully produced with lavish colour illustrations, Unravelled Dreams comes at a remarkably reasonable price, and reveals a substantial facet of imperial history that has previously been neglected. Marsh remains admirably neutral and non-judgemental, even though in retrospect it does seem obvious that some efforts to instigate home manufacture were bound to fail. For example, during the eighteenth century, the Swedish government was so keen to eliminate expensive Chinese imports that it funded local plantations – some even beyond the Arctic Circle – numbering many thousands of mulberry trees. After experimenters reported that menstruating women had no adverse effect on crops, cheap female labour was hired to pick the leaves and keep the worms warm. But despite several decades of effort and investment, many orchards ended up being felled for fuel, victims of the climate and shifting political priorities.

In his prologue, Marsh declares his aim to show that, like silver, sugar and tobacco, ‘silkworms were also at the cutting edge of Atlantic imperialism between the sixteenth and nineteenth centuries’. He certainly succeeds in that goal, and his fine dissection of the industry's ultimate disappearance from Europe and America is of exemplary thoroughness. He could usefully have developed further the undoubted advantages of his unusual focus on non-success, which he describes as a blind spot for academics accustomed to think about winners. For decades, historians of science have been railing against triumphalist accounts endorsing the inevitable march of progress, and this delightfully even-handed interrogation of failure reveals the possibility of a different narrative. Marsh analyses one particular set of failed dreams that were pursued in the past, and his book might prompt reflections on the implications of his research for current scientific endeavours, some of which will surely prove to be similarly evanescent.