The archivist imprint launched by the late guitar genius John Fahey has established an impressive standard for lovingly rendered reissues of all manner of rootsy iconoclasts. The label has topped itself with this lavish seven-CD box honoring the gravelly howl, inventive guitar work, and vivid songwriting of seminal Delta bluesman Patton. The set, which encompasses every session of his brief (1929-34) career, also includes one CD of tracks by Patton-influenced artists, and another of interviews with his contemporaries. Among the illuminating essays is a fascinating book-length dissertation by Fahey. But Patton's genius is best displayed on such riveting tracks as ''Revenue Man Blues,'' ''Prayer of Death,'' and ''High Water Everywhere,'' desolate wails of rage, fear, and dread that resonate as fiercely as ever.