An unknown 17th century German monk left this prophecy, which Ludwig Emmerich recorded in Die Zukunft der Welt (The Future of the World):

"The twentieth century will be a period of terror and misery. In that century everything evil and disagreeable that can be imagined will happen. In many countries the princes will rise up against their father, the citizens against authority, the children against their parents, the pagans against God, entire peoples against the established order. A civil war will break out in which almost all the world will be turned upside down. Financial disasters and ruin of property will cause many tears to fall. Men will be without mind and without piety. Poisoned clouds and rays which can burn more deeply than the equatorial sun, iron armies marching, flying vessels full of terrible bombs and of arrow, fatal flying stars and sulphuric fire destroying great cities. This century will be the most perverse of all because men will raise themselves up and destroy each other mutually."

Today we know that the "poisoned clouds" are those produced by pollution, chemical warfare, or atomic fallout. The burning rays are lasers, the iron armies are tanks, the flying vessels are airplanes, and "fatal flying stars" are rockets.