Page:Indian Journal of Economics Volume 2.djvu/19

 AIT OF ECONOMIC DEVELOPMENT 11 equally applicable, whatever the size or importance of the old trade route, or of the railway to be constructed. We must now see that trade routes must be graded in importance; that the more important a route is in length and in volume of traffic the more does its rocation have a determining' effect upon the lesser trade loutes of the territories it traverses. A close analogy might be drawn with a great r. iver and its tributaries. The alignment of the great trade routes is determined by the principal physical features of a continent--its mountain chains and the passes across them, and its great' rivers--and by the situation of the largest and safest harbors. The great traffic routes across any section o! a continent may, therefore, be deter- mined by physical features far beyond its boundaries. In considering transportation problems, it is necessary, therefore, first of all to consider the country as a whole, and then to take account. of the existing and possible ports in their relation to the great ocean highways of the world. From these considerations it will be possible to map out the great through lines of land communication, which in these days mean the great trunk railway lines. The great trans-continental lines will follow the shortest or easiest routes for connecting the thickly populated areas of the continent, some divergence being caused, however, if political consider- ations so dictate. The trans-continental roues will generally terminate in ports; but this is because any railway lie will always be constructed so as to be used for as many purposes as pozsible, and a share in the ocean-going traffic is valuable. The second class o! through routes consists of those dictated by the situation of the great producing districts of the interior elatively to the coastline. the most convenient and safe ports on Four factors influence the growth of a (1) Its physical configuration binl uch as to