Side by side with this map, ancient monument as it is of antique science, let us place a planisphere representing the world as known in 1840, and on this vast surface we shall find the portion known, and that but imperfectly to Hecatæus, occupying but an infinitesimal space.
Taking these two typical maps as our starting-point, we shall be able to judge of the magnitude of the discoveries of modern times. Imagine for a moment all that is involved in thorough knowledge of the whole world, and you will marvel at the results achieved by the efforts of so many explorers and martyrs, you will grasp the importance of their discoveries and the intimate relations between geography and all the other sciences. This is the point of view from which can best be seen all the philosophic bearings of a wo
