The two-passenger models are being sold to persons of means who have flown or wish to fly and take up friends. After a few years the manufacturers expect there will be a considerable body of these enthusiasts. The greatest sale of these machines, however, will be to the government for the aero mail service. At first two machines will be necessary for every flier in that service, and one in every aerodrome for every one in the air, so with fifty established routes we shall require several hundred machines. Moreover, the manufacturers expect that these machines fitted with either a fuselage or a boat will be employed very extensively by mining companies for carrying precious metals in South America and Alaska. At the present time llamas are used to carry copper down from the Andes. They are so slow and have to descend to the smelters by such devious routes that valuable time is lost in the transportation. By loading the ore into the hold of a flying-boat, which can land on the lakes and ponds in case of engine trouble, the time will be so materially diminished as to reduce the cost of the metal very considerably. Besides, flying in a straight line as the bird flies, at a speed of not less than a hundred miles an hour, will expedite the work of the engineer and the surveyor over the jungles and unexplored and inaccessible portions of South America and Africa, as well as in other distant countries. The conditions in Alaska are analogous, though the climate is different. Dogs and sleds are now used, and they, too, have to travel roundabout routes from mine to town. Of course, an aeroplane fitted with skids or runners can be landed on snow or ice as easily as on land. It now takes two days to sled gold down from one mine in the Yukon to Nome, which could be brought out in three hours by aeroplanes flying over the tops of the mountains. At the time this goes to press Captain Robert Bartlett is so convinced of the feasibility of flying in the arctic regions that he plans to try to fly across the north pole in an aeroplane. During the summer months there are plenty of open spaces on which seaplanes can land in the arctic regions, and flying at 100 miles an hour, it would not take many hours to cross the ice-bound region of the pole itself. Already on the plains of the West and Southwest this type of aeroplane has been found to be more serviceable than the horse in discovering the whereabouts of lost cattle or sheep, because of the range of vision it gives to the shepherd or cowboy and because of its speed and the short distance it covers in reaching its objective. The big bombing bus type is being built primarily for companies or clubs intending to carry passengers from city to city or for cruises from the club-houses.