Among the most successful early engines marketed in the United States were those designed and built by aviation pioneer and inventor Glenn Curtiss. Early Curtiss engines were designed to power motorcycles. The
Salmson water-cooled aero-engines - Wikipedia
What is a Viking Engine? — Viking Aircraft Engines
Piston Engines: Cooling | PPT
Engine Theory: Engine Cooling-Avoiding Meltdown
LIQUID COOLED
Teledyne Continental Motors Voyager-200 Horizontally-opposed Engine | National Air and Space Museum
File:1984 Continental TSOL-300-2 aircraft engine - Hiller Aviation Museum - San Carlos, California - DSC03092.jpg - Wikimedia Commons
Aircraft Oil and Cooling Systems | AeroToolbox
U.S. Navy Aircraft History: The Navy and Liquid-Cooled Engines