Before revision: (Fanny Burney, 1796, Camilla) ''Oxford English Dictionary Plane sailing is based on the assumption that the meridian through the point of departure, the parallel through the destination, and the course line form a right triangle in a plane, called the "plane sailing triangle".
After revision: (Fanny Burney, 1796, Camilla) Plane sailing is based on the assumption that the meridian through the point of departure, the parallel through the destination, and the course line form a right triangle in a plane, called the "plane sailing triangle".