Greatheart Silver is a 1982 science fiction novel written by Philip José Farmer. It is a collection of three of Farmer's stories from the series Weird Heroes published in the 1970s with the title character, a lineal descendant of Thomas Jefferson and Sally Hemings, working for the Acme Zeppelin Corporation as a blimp pilot and private detective.
Greatheart Silver, the thirty-year-old first mate on Acme Zeppelin 8, is the sole survivor of an attack by the Mad Fokker, an air pirate and World War I veteran who was mothballed by the United States government because it could not undo his mental conditioning. Bendt Micawber (the CEO of Acme Corporation and the descendant of Mr. Micawber from David Copperfield) cites his survival as dereliction of duty. Receiving a plastic prosthetic leg as well as his pension as compensation, Greatheart is fired from Acme. During his recovery, Greatheart's fiancee breaks up with him and his Sioux grandmother sends his a birdcage with two ravens inside. He names them Huginn and Muninn after the Norse god Odin's all-seeing ravens.