Gnome-Rhône Mistral Major
The Gnome-Rhône 14K Mistral Major was a 14-cylinder, two-row, air-cooled radial engine. It was Gnome-Rhône's major aircraft engine prior to World War II, and matured into a highly sought-after design that would see licensed production throughout Europe and Japan.
Source: Wikipedia — Gnome-Rhône Mistral Major (CC BY-SA 4.0)