GEOGRAPHY 



2425 



GEOGRAPHY 



raphy, having nothing much to do with the 

 life of man on the earth; but what has a 

 greater influence on man and his activities 

 than the changing seasons, and do not these 

 depend entirely on the movements of the 

 earth among the planets? Mathematical geog- 

 raphy is closely related to astronomy, for only 

 by astronomical means can vast measurements 

 be made or such complicated movements cal- 

 culated. Only the simpler elements of mathe- 

 matical geography are necessary to the ordinary 

 student of the subject only such as will give 

 him an appreciation of distances on the earth's 

 surface, of latitude and longitude, of the in- 

 clination of the earth which determines the 

 various zones, and of the relation of time to 

 longitude. 



The Useful Map. One of the very im- 

 portant branches of mathematical geography 

 is map-making, or, as it is more technically 

 called, cartography. What is a map? It is not 

 a picture, for the lines upon a map do not 

 resemble very closely the objects which they 

 represent. Time was, in the old days of map- 

 making, when attempts were made actually to 

 picture conditions. Rows of little hills, as 

 accurately drawn as might be, showed where 

 the mountains ran; a group of buildings repre- 

 sented a city; trees were sketched to show 

 forest land, and even animals were shown in 

 the wild regions. But to-day the map-maker 

 does not need artistic skill of just this sort, 

 for there has been an agreement as to certain 

 symbols which shall represent certain facts. 

 A map, then, is a representation, and not a 

 picture, and it may show the entire surface of 

 the earth or any part of it. 



A child, asked as to what a map can show 

 him, finds no difficulty in his reply. It shows 

 the difference between land and sea, distin- 

 guishes one country from another, shows riv- 

 ers, mountains, lakes, cities, which city is the 

 capital of a country, and, sometimes, the rela- 

 tive size of cities. These are, indeed, the main 

 things which the commonest type of map 

 shows, but there are coming more and more 

 into use maps which show other things. Par- 

 ticularly well known are the maps which show 

 by shading the varying elevations above sea 

 level; relief maps, they are called. Then there 

 are those which show railroads and roads, 

 those which show mineral productions, vege- 

 table or animal life, or industries. Even the 

 regions in which the various religions prevail 

 are shown on maps. In fact, there are few 

 great facts about the world and its inhabitants 



which cannot be shown more strikingly by 

 means of maps than in any other way. No 

 one who has ever studied maps carefully can 

 fail to realize their appeal. There is the de- 

 light of finding the familiar home city, of 

 tracing the course of the river which is but a 

 little trout stream as it flows by the home farm 

 but swells later to a mighty river, of seeing 

 in graphic form the relative elevation of the 

 everyday surroundings; and then there is the 

 equally great pleasure of picking out the far- 

 away cities whose names have always had a 

 particular charm, of marking the course of the 

 rivers whose names have been sounded for 

 centuries in literature, of finding the part of 

 the world in which great events are taking 

 place to-day. Who, on taking a journey across 

 the North American continent, has not felt 

 the need of a map that he might know when 

 he passed from one state or province to an- 

 other, what river it was that ran beside the 

 train for hours, or where the lines ran that 

 marked the change from one system of time 

 to another? 



These things make up the romance of maps, 

 but there is a very practical and laborious side 

 to them. The child who draws in school a 

 map of Illinois or of Alberta, who carefully 

 sketches the continents, beginning with Africa 

 or South America and coming by degrees to 

 the intricacies of the European or North 

 American coast line, thinks that he has "made 

 a map"; but it is ofie thing thus to draw with 

 the eyes on something which has been already 

 perfected and an entirely different thing to 

 work out a satisfactory method of plotting such 

 maps in the first place. 



For the earth is round and most maps are 

 flat; therein lies the great difficulty. Slit 

 the skin of an orange straight around, letting 

 the cut pass through the ends or "poles," and 

 remove it in two parts. These two hollow 

 hemispheres may well represent the two hemi- 

 spheres of the earth, or rather, their surface. 

 Can these be flattened out on the table without 

 further cutting? Obviously not; and it is 

 just as impossible to represent the surface of 

 the earth accurately on a flat surface. With 

 a sharp knife cut down from the "poles" toward 

 the center, or "equator," of the orange skin, 

 taking care not to sever the hemisphere en- 

 tirely. When a number of slits have been 

 made, the skin may be laid approximately 

 flat on the table, but while the "equator" 

 remains just as it was at first, toward the 

 "poles" there has been considerable spreading. 



