The sixth volume of the collected works of the German writer Karl May (1842-1912), one of the world's most widely read adventure writers, includes the novel "The Treasure of Silver Lake," where the reader again meets with his favorite heroes - Winnetou, Old Shetterhand, Old Firehand, who in the 70s of the XIX century have to engage in an unequal battle with the rabble of the Midwest - the so-called Trumps.