A fascinating tale at the interface of geophysics, maritime history, and the history of science... A remarkable blend of scientific and historical scholarship. Choice 2003 This book illuminates a dark corner of history and science from a unique and well-grounded perspective. By choosing to examine the natural phenomenon of Earth's magnetism within a historical context, A. R. T. Jonkers has found a way to lend both interest and accessibility to what otherwise could be an esoteric topic. Engaging, highly readable, and well written with sound scholarship, Earth's Magnetism in the Age of Sail is a valuable and original contribution to the history of science. Dr. Gregory Good, editor of Earth Sciences History and Director of the West Virginia Cultural Resource Management Certificate Program Jonkers has provided a truly interdisciplinary study that will be accessible to scientists as well as historians. -- Kathy S. Mason History: Reviews of New Books In this ambitious work, the author sets out to rescue from obscurity the thousands of measurements of magnetic declination made by European sailors in the early modern period... The monumental contribution of information and insight brought by this study... will bear fruit well into the future. -- Jordan Kellman International Journal of Maritime History 2005