Attempts at long-distance talking without wires were made from Montauk Point, on the tip of Long Island, to Wilmington, Delaware, and they were successful. This was in 1915. The apparatus was still further improved and then the experiment was tried of talking from the big Arlington station near Washington to Darien, on the Isthmus of Panama. This was a distance of twenty-one hundred miles, and speech was actually transmitted through space over that great distance. That having proved successful, the next attempt was to talk from Arlington to Mare Island and San Diego, on the Pacific Coast, a distance of over twenty-five hundred miles. This proved a success, too, and it was found possible even to talk as far as Honolulu. [Illustration: (C) G. V. Buck Radio Head-gear of an Airman] [Illustration: (C) G. V. Buck Carrying on Conversation by Radio with an Aviator Miles Away] The engineers now felt confident that they could talk across the Atlantic to Europe, and so in October of 1915 arrangements were made to conduct experiments between Arlington and the Eiffel Tower in Paris. Although the war was at its height, and the French were straining every effort to hold back the Germans at that time, and although there were constant demands for the use of radiotelegraphy, the French showed such an appreciation of science that they were willing to lend their aid to these experiments. The Eiffel Tower could be used only for short periods of time, and there was much interference from other high-powered stations. Nevertheless, the experiment proved perfectly successful, and conversation was carried on between our capital and that of France, a distance of thirty-six hundred miles. At the same time, an operator in Honolulu, forty-five hundred miles away, heard the messages, and so the voice at Arlington carried virtually one third of the way around the globe. After that achievement, there was a lull in the wireless-telephone experiments because of the war. But there soon came an opportunity to make very practical use of all the experimental work. As soon as there seemed to be a possibility that we might be drawn into the war, the Secretary of the Navy asked for the design of apparatus that would make it possible for ships to converse with one another and with shore stations. Of course all vessels are equipped with wireless-telegraph apparatus, but there is a decided advantage in having the captain of one ship talk directly with the captain of another ship, or take his orders from headquarters, with an ordinary telephone receiver and transmitter. A special equipment was designed for battle-ships and on test it was found that ships could easily converse with one another over a distance of thirty-five miles and to shore stations from a distance of a hundred and seventy-five miles. The apparatus was so improved that nine conversations could be carried on at the same time without any interference of one by the others.