The story begins with Kepler reading about a skillful magician named Libussa. He falls asleep while reading about her. He recounts a strange dream he had from reading that book. The dream begins with Kepler reading a book about Duracotus, an Icelandic boy who is 14 years old. Duracotus' mother, Fiolxhilde, makes a living selling bags of herbs and cloth with strange markings on them. Duracotus is sold by Fiolxhilde to a skipper after cutting into one of these bags and ruining her sale. He travels with the skipper for a while until a letter is to be delivered to Tycho Brahe on the island of Hven (now Ven, Sweden). Since Duracotus is made seasick by the trip there, the skipper leaves Duracotus to deliver the letter and stay with Tycho.