This book had a tremendous impact on readers in the late 1800s. Written by Ignatius Donnelly, a farmer-politician with no scientific training, it developed a strikingly original theme--that a comet passed close to or struck Earth in ancient times, causing catastrophic changes that later were vaguely recalled in mythologies and biblical tales. Throughout most of the book, Donnelly supports his ideas with convincing geological, archeological, and astronomical arguments. This reprint presents Donnelly's theory of the comet that impacted Earth tens of thousands of years ago, producing layers of gravel (which contemporary scientists attributed to glaciation) and the destruction of an advanced civilization (Atlantis), followed by a years-long cloud cover and extreme cold. A remarkable concept that has also been mentioned in ancient Arabic writings, this theory--and the book in which it is presented--will appeal to readers in many areas of interest: occult enthusiasts, fantasy buffs, and perhaps even some members of the scientific community.