Today, quite as much as a hundred or even two hundred years ago, major libraries throughout the world often seem inordinately conscious of their holdings of books that were printed in or before the year 1500. The cult of the incunable is with us still, and it is Kristian Jensen's aim to explain its genesis. His book had its own origin as the Lyell Lectures in bibliography, delivered at Oxford in 2008: it seems closely to follow the lecture form in its very clear structure and reiterated reprises.

A great many aspects of the history of incunables from the seventeenth century to the mid-nineteenth century are touched on, and numerous topics are minutely examined, and yet all is placed in the broadest of intellectual contexts. The reader is brought right into a whole series of interrelated debates about the value of incunable texts (classical and medieval), the relative positions and merits of private collectors and publicly funded libraries, and the physical treatment of the books themselves. At times, it is even hard to distinguish Jensen's own attitudes from the opinions expressed by his dramatis personae (see, e.g., 34–35, where it is unclear whether it is he or the Assemblée législative that has seen coats of arms as feudal symbols and has come up with the term “genealogical charter”). His strength is that he has made good use of archival materials—most notably, the institutional records of the Bodleian Library and the personal papers of George John Spencer (1758–1834), second Earl Spencer. The Bodleian built up what is still the largest collection of incunables in any European university library, while Spencer at the same time was putting together one of the finest collections of incunables ever formed (still largely intact, in the John Rylands University Library at Manchester). Closer to Jensen's heart, perhaps, is Francis Douce, politically radical but socially conservative, whose papers afford lively aperçus on the social mores of the wealthier players in the book-collecting world.

Very broadly speaking, Jensen begins by providing a broad context for the interest in early printing (and specifically in incunables); in the course of six chapters, he works toward the particular, the incunable as physical object. As he does so, his enthusiasm palpably increases, and the reader will perhaps be the more readily persuaded by his arguments. Throughout, this is a highly didactic book, which never lapses into narrative or the merely descriptive. However, Jensen's archival research seems to have been at its most rewarding when he focuses on the relations between individual collectors and dealers, and—quite deliciously, at times—those who were really the one but sought to be the other. Statistical charts are provided only for the Bodleian Library's purchases of incunables, 1700–1861, and the personalities and motivation of those who led the Bodleian into its purchases are excluded from consideration. Earl Spencer's activities are woven into all parts of the text, rather as this peer contrived to fit his weekly or even daily visits to antiquarian booksellers into his daily political life—which included being First Lord of the Admiralty (1794–1801) during the war with the French, whose own national library was one of his principal competitors in the international rare books market.

Having contextualized and described the incunable dealers' and collectors' world, Jensen turns in his last chapter to a consideration of how the books themselves were treated. His intellectual framework works very well here, in explaining why the incunables were altered in what might to our eyes seem a cavalier way, being shorn of their original bindings, de-medievalized, and rebound as contemporary trophies. A good parallel is drawn with the way in which damaged classical statuary was in the same period restored and perfected. Jensen then concludes with a look at how the late eighteenth century's reformulations were in the early to mid-nineteenth century in a large measure taken over by the national libraries (such as the British Museum) that were coming to replace the great private collectors. Here, again, fruitful parallels are drawn with national galleries of art, which also aimed to offer equal opportunities of study to all who were interested.

There has never before been such an intellectually ambitious study of this sort in the field of postmedieval book-collecting and library formation. Jensen has aimed high, and in a very large measure, he has succeeded in rationalizing a myriad of intersecting ideas, forces, and trends. Decades of working with incunables have enabled him to write with authority and perception, and he combines these with utter clarity. His work is not faultless: he has spread himself so widely that this was perhaps inevitable. Franciscans are friars, not monks (145); muriatic acid is better known as hydrochloric acid (155); there is inconsistency about Bodleian Library acquisitions of incunables before 1789 (contrast 3, 85, and 152–53); and Thomas Grenville was not a knight. The book itself is sadly bereft of the color that would make better sense of much of what is said about the sumptuousness of some of the rebindings, and its index is quite inadequate.

It is also undeniable that more might have been said about certain topics. The German eighteenth-century writers about the history of printing get rather short shrift, “black-letter” and “gothique” fonts (and their own cults) are hardly touched upon, and the importance of the book trade in creating the market for incunables is underplayed (it is nowhere made clear that it was purchases at two auctions in London and Amsterdam, of the Pinelli and Crevenna collections, that were pivotal in making the Bodleian Library such a possessor of incunables; nor is there discussion of what prompted these interventions). Nevertheless, that one is left asking for more should be seen as a tribute to this pioneering work of high originality and persuasive scholarship.