The Adams Company, Dubuque, Iowa / F.O. Farwell, engines for gyrocopters. Adams-Farwell 36 hp 5-cyl rotary engine 4.25 in × 3.25 in (108 mm × 83 mm) Adams-Farwell 50 HP; Adams-Farwell 55hp 5-cyl rotary 5.25 in × 5 in (133 mm × 127 mm) Adams-Farwell 63hp 5-cyl rotary 5.625 in × 5 in (142.9 mm × 127.0 mm) Adams-Farwell 72hp 5-cyl rotary 6 in × 6 in (150 mm × 150 mm)