This most impressive work of historical scholarship is the result of research conducted over the better part of two decades by Stephen Bell, who is indubitably the world authority on Bonpland. Painstaking labour in the archives of six countries and across a plethora of primary and secondary printed sources (many of which Dr Bell is obliged to correct and augment) has resulted in a much delayed but thoroughly deserved restoration of Bonpland's reputation in what might be termed a ‘post-Humboldt’ phase. That period might be said to last from at least 1817 (and arguably earlier in the public eye), which means that it corresponds to the bulk of Bonpland's life, although he and Humboldt maintained a lively if erratic correspondence throughout (Humboldt wrote a final letter in 1858 unaware of the death of his travelling companion and fellow scientist on the famed voyage of 1799–1804). The book's title is justified because Bonpland's reputation was already outshone by that of Humboldt before the former returned to the Americas in 1817. Until 1830, and particularly in 1822, such a return had been a dream for Humboldt too, but his yearnings were never realised. Given Bonpland's near-decade-long imprisonment in Dr Francia's Paraguay during the 1820s, one can understand both why the European profile of the slightly younger French doctor and botanist became more that of a distant cause célèbre and that of the Prussian scientist continued to mutate into that of regional statesman and leading public intellectual of the North Atlantic world. Bell understandably takes most of the Humboldt story as already read, not least because there is a great deal to be related about Bonpland's ‘second life’ that possesses autonomous value and rich interest. So, those unfamiliar with the 1799–1804 voyage – one of the great scientific enterprises of the modern world – should not look to the introduction here for a proper rehearsal of its qualities.

Bonpland's subsequent life and the scientific, medical and agricultural labours that occupied him right up to his final weeks in a broad upper Platine zone bordered by the rivers Paraná and Uruguay (including the enforced years north of the Paraná in Paraguay) have long been the stuff of imagination and sometimes determined invention. The paucity of documentary evidence, combined with an illustrious reputation in the context of burgeoning romanticism, serves to fortify a kind of contra foundational fiction, with Bonpland serving as a talismanic mix of Old World scientific traveller, displaced chorus-master on early republican society in the Americas and, occasionally, lightning rod for the anti-imperialist cause. Bell's account begins with a rare and most welcome invocation of Sybille Bedford, and it is hardly under way before we are reminded that Bonpland is a figure whose presence is to be found in the work of Daniel Kehlmann, Augusto Roa Bastos and Gabriel García Márquez. These, though, are simple name-checks; Dr Bell is a rigorously document-based scholar who purposefully will not venture where the evidence does not lead. Researchers who have themselves laboured for years in disordered depositaries and amongst scattered personal papers, ever tempted to triangulate in order to firm up the most beguiling hypothesis but compelled by professional circumspection to stick with what is available and verifiable, will certainly appreciate why the author steers clear of the more exotic attributions and suggestions. Yet, on occasion this severe approach deprives us of legitimate discussion – not just of the febrile political atmosphere of Rivadavian Buenos Aires and then the rigours under Rosas, but also of Bonpland's personal life and particularly the role of his French wife Adeline and step-daughter Emma, for whom we do in fact have sufficient materials to justify a little more than the parsimonious mentions offered here.

Nonetheless, one can appreciate caution in terms of personal biography in the light of the considerable interdisciplinary controversy raised in the early 1990s by the literary scholar Mary-Louise Pratt over the figure of Humboldt in her very popular Imaginary Eyes (1992). At the core of that text, Bonpland's companion served – mostly alone, but occasionally with Aimé himself also appearing in a truncated narrative – as proto-imperialist entrepreneur in the ‘contact zone’, the original harbinger of subsequent capitalist depredation in Latin America. Bell teaches geography as well as history, and for many geographers – Aaron Sachs was perhaps the most provoked and energetic in retort – Pratt's work was little more than a sharp piece of ideological and teleological manipulation, its jazzy post-colonial paradigm rendering any serious primary research otiose if not positively risky for such a neat iconoclastic thesis. Over subsequent years – and not least in 2004, when the bicentenary of the Humboldt–Bonpland voyage was publicly commemorated – the quality of scholarly research on that experience, both as a discrete Enlightenment ‘event’ and as part of a longer scientific ‘process’ including Darwin and beyond, has largely supplanted a rather arid academic spat. It is, then, something of an irony to find in Bell's text a fair amount of hard empirical evidence for Bonpland as precisely the kind of risk-capitalist that Pratt had earlier labelled Humboldt. Now, instead of guano, it is the possibilities of commercial cultivation of yerba maté and the breeding of merino sheep that occupy Bonpland's schemes and precarious resources. The resulting picture is rather unsurprising – Bonpland's original 1805 pension from Paris was far less frequently available than some of the literature allows, and how was any farmer to live in the Americas in the 1830s without engaging in a quotient of market relations?

It is, by the same token, a complex and fascinating picture, adding richly to our growing knowledge of the great unevenness of society and civilisation north of the Plate in the early republican era. Those who have hitherto been content to repose on broad social science categories such as ‘communications’ or ‘subsistence agriculture’ should enjoy the suggestively revisionist accounts of travel by canoe and mule (private animals often being exchanged for the stock of the local state) and the salience of the lambing season and rains to rustling and military activities. Bell gets the very best out of his materials in etching this monographic portrait, as well as augmenting the larger, cosmopolitan portrait that we know rather better by dint of those letters that crossed the Atlantic eastwards. As a professional geographer, he helps the reader with the (many) scientific terms required for a close understanding of Bonpland's experiments, and his department at UCLA has provided us with a fine map through which to trace the peregrinations of four decades. The book is densely populated with learned footnotes (wherein one can almost follow a subsidiary story as well as the comprehensive references). It is lightly but usefully illustrated, with the inclusion of a newly identified daguerrotype from the 1850s providing a vivid image of a man whose life was extraordinary enough not to need hyperventilated description – even if one rather wishes that, prior to his modulated and magisterial general conclusion, Bell might have ventured a considered opinion on the more colourful accounts of Bonpland's death.