This is the rich history of the most important navigational device of all time, the magnetic compass, born of the need for a reliable means of negotiating treacherous sea routes around the globe. Compass chronicles the misadventures of those who attempted to perfect the instrument—so precious to sixteenth-century seamen that, by law, any man found tampering with one had his hand pinned to the mast with a dagger. Part history, part adventure, this book is a compelling tribute to human ingenuity—and the mysteries of the sea.