Before revision: A saddle can vary from a sharp, narrow gap to a broad, comfortable, sway-backed shallow, valley so long as it is both the high point in the sloping faces which descends to lower elevations and the low area between the two (or three or four.)
After revision: A saddle can vary from a sharp, narrow gap to a broad, comfortable, sway-backed , shallow valley so long as it is both the high point in the sloping faces which descends to lower elevations and the low area between the two (or three or four.)