Held at Philadelphia for promoting useful knowledge.

"This is the first book that focuses on Benjamin Franklin as a swimmer. Franklin thought swimming a valuable activity and swam whenever he could wherever he was. We can see Franklin's personality emerge through the lens of swimming, which offered him entrée into London society as a young man. The book includes excerpts from the journal of Benjamin Franklin Bache, Franklin's grandson"--

As the essays in this collection make plain, Isaiah Berlin invented neither the term "Counter-Enlightenment" nor the concept. However, more than any other figure since the eighteenth century, Berlin appropriated the term, made it the heart of his own political thought, and imbued his interpretations of particular thinkers with its meanings and significance. His diverse treatment of writers at the margins of the Enlightenment, who themselves reflected upon what they took to be its central currents, were at once historical and philosophical. Berlin sought to show that our patterns of culture, manufactured by ourselves, must be explained differently from the ways in which we seek to fathom laws of nature. Many of the essays in this volume were prepared for the International Seminar in memory of Sir Isaiah Berlin, held at the School of History in Tel Aviv University during the academic year 1999-2000.

The American Philosophical Society exhibition, Curious Revolutionaries: The Peales of Philadelphia (April-December 2017), curated by Andrew W. Mellon Postdoctoral Fellows Drs. Diana Marsh and Amy Ellison, offered visitors a look at the lives, accomplishments, and legacies of Charles Willson Peale and his talented family. Expanding on the exhibition, "The Art of Revolutions" conference, cosponsored by the American Philosophical Society, the Museum of the American Revolution, and the Philadelphia Museum of Art, explored the role of imagery in influencing and giving meaning to the political revolutions that defined the late 18th and early 19th centuries. The conference was held October 26-28, 2017, at the American Philosophical Society. Included here is a selection of the talks presented at the conference, revised and updated. The volume also contains an introduction by Cathy Kelley and a compelling preface by Patrick Spero, Librarian and Director of the APS Library.

After the telescope became known in 1608-1609, a number of people in widely separate locations claimed that they had such a device long before the announcement came from The Hague; in the summer of 1608, no one had a telescope, in the summer of 1609, everyone had one. For a number of years author Rolf Willach has quietly tested early spectacle lenses in museums and private collections, and now he reports on this study, which gives an entirely new explanation of the invention of the telescope and solves the conundrum mentioned above. Willach is an optical engineer and independent scholar who worked for several years in the Department of Physics at the Institute of Astronomy in Bern. He has written extensively on the history of the development of optics and the telescope.