The most rapid change in the commercial map of the world wrought in centuries will be witnessed during the years following the completion of the Panama Canal. Cities that heretofore have been mere way stations on the international routes of trade will grow into rich centers where the new roads of the commercial world will cross. On the other hand, cities which in the past have gloried in a trade supremacy of international recognition will see themselves displaced and their prestige lost. The readjustment will not be the matter of a day or a year; even a generation may pass before it is completed; but the ultimate changes will certainly be greater and more world-encompassing than anyone now can forecast. The capture of Constantinople by the Turks was directly responsible for the discovery of the New World. It cut off the cities of the Mediterranean from communication with India, and sent Columbus westward in quest of another passage, which could not be obstructed by the Mussulman tyrants of the East. At last the Panama Canal is to afford that passage, and to bring the whole earth into smaller compass. Of course, the United States will be the first to realize the great benefits of the canal. It will double the efficiency of the American Navy by permitting it to concentrate its forces on either ocean in shorter time, by weeks, than can be done by any other nation; consequently, it will add to American military prestige throughout the world. The benefits immediately accruing to the people of the United States will be as great in a commercial way as in military advantage. As the capture of Constantinople caused the up-building of many notable regions through the transformation of international trade routes, so will the completion of the Panama Canal open up new markets and new opportunities to the Mississippi Valley, the world's greatest granary. Its grain and meat products, loading by way of Gulf ports, can go to the ends of the earth with but little outlay for expensive rail transportation. It is even probable that the great awakening incident to the opening of the canal, may hasten the day when the Lakes-to-the-Gulf waterway will be an accomplished fact and when ships may load in Chicago, Detroit, Cleveland, St. Paul, and Minneapolis and sail directly to the ports of the world, thus beginning an era of commercial development surpassing even the wonderful growth of the half century just closed. Pittsburgh may then be able to send its tremendous output of manufactures to all parts of the world without transhipment; Kansas City will feel the stimulus of the new waterway; and the Pacific coast, long cut off from the eastern section of the United States by high mountain barriers that have been only partially overcome by railroads, will find its great resources within marketable distance of the Eastern States.