Da Milano A New York

Authors and Subjects

Leonardo da Vinci’s Giant Crossbow

Although Leonardo’s Giant Crossbow is one of his most popular drawings, it has been one of the least understood. "Leonardo’s Giant Crossbow" offers the first in-depth account of this drawing’s likely purpose and its highly resolved design. This fascinating book has a wealth of technical information about the Giant Crossbow drawing, as it’s a complete study of this project, though this is as accessible to the general audience as much as it is also informative with new discoveries for the professors of engineering, technology and art. The book explores the context of Leonardo’s invention with an examination of the extensive documentary evidence, a short history of the great crossbow and ballista, the first accurate translation of the text and the technical specifications, and a detailed analysis of Leonardo’s design process for the crossbow, from start to finish. Dozens of preparatory drawings, along with the recent discovery of nearly invisible metal stylus preparatory incisions under the ink of the Giant Crossbow drawing, are evidence of Leonardo’s intent to offer engineers and other viewers a thorough design of the massive machine. The book proposes these new discoveries with the help of a strategy that had been at the core of Leonardo’s working philosophy: the proportional method. As proven with an analysis of the Giant Crossbow project, he used a consistent approach to 1/3rd proportions throughout the design and drawing process and employed this kind of proportional strategy at the start of almost every important project. Thanks to this proof of his knowledge of geometry, evidence of his studies of impetus and force, and thanks to the highly polished and complex nature of the Giant Crossbow design, a later date for the drawing is proposed in the present book, associating the drawing with his drafting capabilities around 1490-93.

Deaccessioning and Its Discontents

The first history of the deaccession of objects from museum collections that defends deaccession as an essential component of museum practice. Museums often stir controversy when they deaccession works—formally remove objects from permanent collections—with some critics accusing them of betraying civic virtue and the public trust. In fact, Martin Gammon argues in Deaccessioning and Its Discontents, deaccession has been an essential component of the museum experiment for centuries. Gammon offers the first critical history of deaccessioning by museums from the seventeenth to the twenty-first century, and exposes the hyperbolic extremes of “deaccession denial”—the assumption that deaccession is always wrong—and “deaccession apology”—when museums justify deaccession by finding some fault in the object—as symptoms of the same misunderstanding of the role of deaccessions in proper museum practice. He chronicles a series of deaccession events in Britain and the United States that range from the disastrous to the beneficial, and proposes a typology of principles to guide future deaccessions. Gammon describes the liquidation of the British Royal Collections after Charles I's execution—when masterworks were used as barter to pay the king's unpaid bills—as establishing a precedent for future deaccessions. He recounts, among other episodes, U.S. Civil War veterans who tried to reclaim their severed limbs from museum displays; the 1972 “Hoving affair,” when the Metropolitan Museum of Art sold a number of works to pay for a Velázquez portrait; and Brandeis University's decision (later reversed) to close its Rose Art Museum and sell its entire collection of contemporary art. An appendix provides the first extensive listing of notable deaccessions since the seventeenth century. Gammon ultimately argues that vibrant museums must evolve, embracing change, loss, and reinvention.