The next great feat of the aeroplane is the crossing of the Atlantic Ocean, and that may not be far distant, for at the time of writing half a dozen aviators are planning the attempt, but even more important than that, even more important than the development of the aeroplane for war scouting, is the development of the aeroplane as a faithful servant of the people who are quietly going about their own everyday business. The time will come when the readers of this may send their mail by aeroplane, take pleasure rides in the aeroplane instead of the automobile, and even make regular trips on regularly established aeroplane routes, buying their tickets at the great central aeroplane stations as they would buy railroad tickets in the Grand Central or the Pennsylvania stations to-day, taking their seats in comfortably arranged aero cars, and being whisked in a few hours from one part of the country to the other, and even from one side of the ocean to the other. CHAPTER IV ARTIFICIAL LIGHTNING MADE AND HARNESSED TO MAN'S USE OUR FRIENDS INVESTIGATE NIKOLA TESLA'S INVENTION FOR THE WIRELESS TRANSMISSION OF POWER, BY WHICH HE HOPES TO ENCIRCLE THE EARTH WITH LIMITLESS ELECTRICAL POWER, MAKE OCEAN AND AIR TRAVEL ABSOLUTELY SAFE, AND REVOLUTIONIZE LAND TRAFFIC. "How would you like to send a signal clear through the earth with your wireless outfit and get it back again on your receiving instrument as clear and strong as at first, just about the same way you hear the echo of your voice when it rebounds from a mountainside or a big building?" asked the scientist one day while his young friend was telling him about his amateur wireless experiments. "I don't see how I could," answered the boy. "No, of course you don't," said the boy's friend, "for it took Nikola Tesla, 'the wizard of electricity' almost a lifetime to work out the invention by which he could do that, but if you like we will go and see Doctor Tesla and ask him to tell us about his wonderful experiments. "You see this is a series of inventions by Tesla, and wireless telegraphy is only a small part of it. You remember the other day you told me of having read about aeroplanes equipped with wireless. Just think, Tesla's invention will make it possible for airships to be propelled and operated all by electricity sent without wires. The whole broad plan is called the wireless transmission of power, and that simply means that electricity can be transmitted without wires for all the uses we now have for it, as well as for a number of entirely new and hitherto unknown devices." The boy was delighted with the prospect of seeing the great scientist Tesla, about whom he had read so much, and began to ask his older friend a thousand questions about the man, his work and life.