Bird's-eye View

Bird's-eye View is a term applied generally to modes of perspective in which the eye is supposed to look down upon the objects from a considerable height. In sketching or drawing a locality for military or economical purposes, this kind of perspective is always used. The great difficulty is to represent at the same time the relative heights of mountains and steepness of acclivities. But the more usual kind of bird's-eye view differs from the common perspective picture only in the greater height of the horizontal line.