CHAPTER V

GENERAL ASPECTS OF THE SURFACE AS SEEN FROM THE AIR

(FIGS. 12 TO 18)

When a region is viewed from an altitude of several thousand feet the observer can readily imagine himself looking down on a large map. The chief features stand out prominently, the smaller to a lesser degree. Mountains, rivers, and the seashore are

especially conspicuous. Streams appear as smooth, winding ribbons--glistening if the sunlight reflected from them enters the eye, dark if the bright rays are reflected away from the eye. Railroads can easily be traced and towns recognized by their form. Concrete roads and others of light-colored material are plainly visible. Those built of dark-colored material appear less prominently. Something even of the character of the forests can be ascertained--whether evenly timbered or partly of primary and partly of secondary growth; whether intact or partly burned over; whether consisting chiefly of one species of trees or of many. The cultivated fields and their relations to roads, streams, and forests are conspicuous. Towns and cities are spread out like panoramic views in which are strikingly visible the residence and manufacturing centers, the layout of streets, the systems of parks, the position of suburbs, and the relation of these to routes of transportation and travel--roads, railroads, and waterways. These and many other features of the landscape--swamps, marshes, buildings, trees, orchards, and many lesser details--are recognizable and are all recorded on the

photographic negative. So faithfully does the camera reproduce all the horizontal features within its range of vision that it is conceivable that a photograph correctly dated might become a valuable record in cases of boundary disputes or other litigations involving the position of fences, fields, roads, or even streams, at a given date.