[CHARTS AND MAPS]
Need of maps. Maps are useful and necessary for many purposes. Only by means of a correct map or globe can a clear idea of the geography of a region be given. An attempt to convey the same information by a written description would in comparison be both cumbersome and obscure. Even by passing over an extensive region a man unaided by instruments will obtain only a rather crude notion of the relations, which he could clearly see on a good map. The importance among the human arts of the making of maps is indicated by the references to them in very early historical records, and by the skill in map drawing shown by some of the primitive peoples of to-day. This skill exists particularly among races whose mode of life gives them a wide horizon, as for instance the Eskimos. An interesting instance of this was the case of Joe, an Eskimo guide, who, in 1898, before the surveys of the Yukon delta were made, drew a map of the Yukon mouths with much more complete information than any previously available.
Without attempting to enumerate in detail the special uses for maps, in the broader sense they may be said to be essential for commercial, engineering, military, scientific, educational, and political purposes.
Early geography and map making. The oldest map known is a plan of gold mines in Nubia, drawn on a papyrus. This is of the thirteenth century B.C., and was found in Egypt.
In the earliest historic times men believed the earth to be a flat surface of nearly circular outline, a natural inference for those with limited outlook and communication. Later the idea was introduced of the ocean as a river bounding the earth disk. The spherical theory of the earth was, however, early accepted by learned men, and was demonstrated by Aristotle (384 to 322 B.C.), who used as proofs the earth's shadow on the moon, and the change in the visibility of the stars in traveling north or south. Crates constructed a terrestrial globe in the second century B.C.
There is no Greek or Latin map extant of earlier date than the time of Ptolemy, but there are references showing that maps were in use. One of the first of such passages in Greek literature is the interesting comment of Herodotus written in the fifth century B.C., "but I laugh when I see many who already have drawn the circuits of the earth, without any right understanding thereof. Thus they draw Oceanus flowing round the earth, which is circular, as though turned by a lathe, and they make Asia equal to Europe."
A map of the world was drawn by Anaximander, 560 B.C. A hundred years later Democritus drew a map having an oblong shape, and taught that the width of the world from east to west was one and a half times its extent from north to south, a conclusion based on his travels eastward as far as India. This theory, which was for a time accepted, has left an enduring mark in the words longitude and latitude, originally signifying the length and the breadth of the earth.
The first application of astronomy to geography was made by Pytheas, who about 326 B.C. obtained the latitude of Marseilles by an observation of the altitude of the sun. Dicearchus in 310 B.C. determined the first parallel of latitude by noting places where on the same day the sun cast shadows of equal length from pillars of equal height. Eratosthenes (276 to 196 B.C.) was the first to compute the circumference of the earth from observations of the altitude of the sun at Alexandria and at Syene in Upper Egypt and an estimation of the distance between these two places. Ptolemy, a Greek of Alexandria, in the years from 127 to 151 A.D. wrote extensively on geographic subjects, and collected into systematic form all geographic knowledge then existing; he was the greatest geographer of early history.
In the ten centuries which followed, part of the early advance in this science was obscured, and the theory that the earth was a flat disk surrounded by the sea again became prevalent. The voyages of discovery of the middle ages, however, led to a rapid development of geographic knowledge.