Extension of air traffic is especially probable in industrial and agricultural countries of large area, such as the United States, Canada, Australia, India and the South American republics. Another projected development with immediate possibilities is the linking of regions that are separated by a comparatively narrow expanse of water. Obvious examples, in addition to Britain and France, are England and Ireland, the Mediterranean coast of France and the Mediterranean coast of Africa, and Florida and Cuba. Traffic across the ocean or a great lake offers to air travel the best time-saving inducement. To connect two places separated by one hundred and fifty miles of water, an average steamship needs ten hours. A passenger on it must spend at least one night away from home, while transacting his business. An air passenger covers the same distance in one and one-half to two hours, and can return on the same day. For such transport the seaplane and the flying boat will have their chance. Besides the carriage of passengers, mails and valuable freight, aviation will have many additional functions. Maps may be made and checked with absolute accuracy by means of aërial photography. Another important function of the aëroplane and the aërial camera is to explore and prospect undeveloped districts. In places remote from the ordinary facilities of civilization aircraft may be used for the discovery of fire, flood and lawlessness. Already the Canadian Northwest Mounted Police have captured wrongdoers by means of aëroplane patrols. Aircraft offer particular advantages as carriers in regions where the natural obstacles on the ground prohibit railway or road transport. In Alaska valuable metals and furs are brought to civilization on sleds drawn by dogs, over paths that are circuitous and dangerous. They could be taken in safety, and with an immense saving of time, by aëroplanes fitted with skids suitable for landing on ice and snow. Again, copper is transported from mines in the Andes by llamas, which are slow and must jog over devious tracks. Aëroplanes could make the journey directly and speedily, from mine to coast, without regard to precipice, marsh or forest. South America is likely to be a happy hunting-ground for aëronautical pioneers. The mountain-range of the Andes, which for hundreds of miles sharply divides America into two parts, gives aviation an incontestable opportunity. The eastern section of South America could be brought days nearer the western section by high-climbing aircraft, which would provide a pleasant alternative to the roundabout, uncomfortable journeying now necessary. The air mails between the two great commercial centers of South America--Rio de Janeiro and Buenos Ayres--should also save many days of valuable time. Many owners of ranches and plantations in the Argentine, Uruguay, Paraguay and Brazil are buying aëroplanes to bring their isolated, up-country properties in closer contact with the towns.