Alice and her father had been invited, the next day, to Ralph's laboratory, as he wished to show them some of his latest discoveries. They found him sitting in front of his desk while he was engaged in dictating scientific data to thin air. "Ah!" said Alice, as she entered, "you are evidently using some of the methods of my kidnapper, since you seem to be dictating to an invisible secretary!"
"Nothing so complicated," said Ralph.
Ralph, who then welcomed them, denied the charge, and went on to explain to his party his new invention.
"The evolution of letter-writing has been a slow and painful one. Our remote ancestors, many thousands of years ago, carved their letters in stone slabs. Later on, the more civilized Egyptians wrote their letters upon papyrus. Still later, upon the invention of paper and ink, communications and letters could be written much better and faster in that improved manner. Later still, the typewriter came into use.
"All of these methods had one great drawback. It was possible to easily falsify such records. While there had been handwriting experts, it happened very frequently in olden times—too frequently, in fact—that a signature on such an important document as, for instance, a will,[Pg 128] was forged, and it became a question for handwriting experts to decide whether the signature was genuine. But even the handwriting experts were not always right.
"It has often occurred to me that it should be possible to use the human voice as its own document so that it could be preserved in a different manner than the phonographic method discovered in the 20th century. Of course, under that method it was possible for one to speak one's last will and testament, but it was a clumsy way and was rarely used on account of its high cost. Furthermore it was difficult to make copies of a talk. Then, too, the disc or cylinder upon which the phonographic records were made were very fragile, and could be broken, either accidentally or purposely.
"The method you see me using is phonetic, and it is practically impossible to falsify such a record. Watch how the machine works."
Ralph reseated himself at his desk and started to talk. Facing him on the desk was a machine of about the shape of an old-fashioned typewriter, except that there were no keys. There were a few dials and knobs and from the top of the cabinet a white sheet of paper slowly emerged as Ralph dictated. When he had finished, he pressed a button and the entire sheet was ejected. It was covered with queer-looking wave lines, similar to the lines made by a seismograph when recording earthquakes—queer little parallel lines with humps at the tops that increased from very short wave-like scrolls to long ones. The entire sheet was covered with these lines in indelible ink. Ralph showed Alice the page and went on explaining:
"The page which you see here is an exact record of my voice, but just as no two fingerprints are alike in this[Pg 129] world, no two voices are alike either. Each has certain characteristics produced by certain overtones in the voices of the various individuals. The pronunciation of individuals varies, so does the intonation, so does the speed of talking, so does the timbre of the voice, and a hundred other differences that to an expert are observable immediately.
"Suppose, then, during my life I have recorded a great many documents similar to this one. The waves traced on this piece of paper have certain characteristics, which are entirely individual. Here are two sheets of paper, both containing the Lord's Prayer, but spoken by two different individuals in my office. Both of these individuals have voices that are very nearly alike, yet, you can see how great a difference there is between the lines. On one sheet the lines are much heavier and swing in quite an apparently different manner.
"By reference to authentic documents of this character, it will be impossible to falsify any record by having some one else make such a spoken record. A will, or any other important document, will, in the future, be made by this machine and will do away with many court cases and much business squabble, and much shirking of responsibility.
"Furthermore, by my method it is possible with the same machine to make as many as twenty-five copies at one time, while the original is being made. This is done by a chemical process in the machine itself, the copies being simply thin chemical papers which are being developed at the same time as the voice-writing is being made.
"Reading these pages is not as difficult as you might think. It would be necessary, however, to know the pho[Pg 130]nolphabet. The phonolphabet is not very much different from the alphabet that you now know. Every syllable and every consonant used by you makes a certain impression in my machine, and while it may vary, as explained before, still it remains roughly the same, exactly as handwriting by different persons may vary, but still you can read because the characteristics are the same. The same is true of my machine. By studying the characters of the phonolphabet, it is possible, within a few weeks, to learn how to read a phonetic letter, with the same ease that you read a handwritten or typewritten letter.
"I expect that in the schools of the future children will be taught the phonolphabet so that every one will be able to read phonetic records.
"Another feature of my invention is that if you do not wish to read the letter you can listen to it." Saying so, Ralph inserted the letter into an odd-shaped cabinet, which had a slot at the top. Two grippers slowly began to draw the paper into the inside of the machine. Ralph turned two knobs and pushed a button, and within a few seconds his own voice was heard with unmistakable clarity repeating what he had said fifteen minutes before.
"This machine, likewise, is very simple," said Ralph. "The ink tracing on the paper record is opaque, while the paper itself is more or less transparent under a strong light. A light-sensitive cell on the other side slowly moves from left to right, taking off the entire phonetic record, as it were. This light-sensitive cell moves in the same ratio and with the same speed that I originally dictated, and the words are reproduced exactly as I spoke them, by means of a loud-speaking telephone coupled to an amplifier.
[Pg 131]
"Thus it is now possible to have a double record; an audible and a written one, and with the two it is practically impossible to falsify records.
"As you know, there have been some big embezzlement scandals recently and it was not always possible to convict those suspected due to the clever methods which these swindlers used.
"One great advantage of the new system is that it is done entirely by machine and does away with the human element. I do not require my real secretary when I dictate. I sit alone in my study or office and simply talk."
"There is one unique place, I am sure you will be interested in." Ralph led the way to the elevator and they quickly shot up to the roof, where they boarded one of Ralph's flyers and within a few minutes were heading north. The machine rose until they were up about 20,000 feet. The cold made it necessary to turn on the heat in the enclosed cab. In the distance, just ahead there shortly appeared a brilliant spot of light suspended in the dark sky, which quickly increased in size as they approached. From a distance it appeared like an enormous hemisphere with the flat side facing the earth below. As they drew close, they could see that it was a great city suspended in the air apparently covered with a transparent substance, just as if a toy city had been built on a dinner plate and covered with a bell-shaped globe.
They alighted on the rim, at a landing stage outside the transparent covering. They were soon walking along a warm, beautifully laid out street. Here was neither bustle nor noise. The deepest calm prevailed. There were small houses of an old-fashioned design. There were shops in[Pg 132] great profusion. There were playgrounds, neatly-laid-out parks, but without looking at the humans that were walking around, the visitors felt as if they had gone back many centuries.
There were no power roller skates, no automatic vehicles. There were no aeroflyers beneath the glass ceiling. Instead a serene calm prevailed, while people with happy expressions on their faces were leisurely walking to and fro.
Very much puzzled, Alice wanted to know what this mysterious glass-encased city was.
"This," explained Ralph, "is one of our many vacation cities that I hope will soon dot every part of the world. People are living entirely too intensely nowadays and with the many functions that they have to perform, with all the labor-saving devices they have, their lives are speeded up to the breaking point. The businessman or executive must leave his work every month for a few days, if he is not to become a wreck. Heretofore we have sent him to the mountain tops or to the seashore; there he found no rest. The noise, even on top of the mountains, due to aeroflyers and other vehicles, did not give a man a real rest. On our floating city there is absolute rest. There is no noise, no excitement, not even a radio telephone.
"The city, 20,000 feet above the ground, is floating in perfectly clean and uncontaminated air. This air, while less dense than that further down, is renewed automatically every few hours. It is invigorating, just the same as mountain air with all its benefits.
"The roof is made of steel lattice work, thick glass panes being fitted in between the steel frames. The shape[Pg 133] is in the form of a huge dome covering the entire city, which measures about a little over a mile in circumference. The height of the center of the dome from the floor of the city is about 200 feet. At night the city is illuminated by cold light from high frequency wires running below the dome, similar to the system now used to light up our cities.
"The floor upon which the entire city rests is steelonium, and the city is held up by means of anti-gravitational impulse. By neutralizing the gravity for the area below the floating city and a little beyond it, it is possible to keep the floating city at any distance from the earth. In other words, we use a gravitational 'screen,' and then build a city on top of this screen.
"By charging the gravitational screen at a very high potential, we nullify gravity and as the city no longer has any weight it can be placed on any level and remain there practically indefinitely. A few air propellers keep t............