PROFESSOR MYERS IN HIS "SKYCYCLE."
And he spoke of the strangest illusions of sight. The balloon is always standing still to the person in it, while the earth rushes madly along, forty, sixty, ninety miles an hour. As you shoot up the first half mile the ground beneath you seems to drop away into a deepening bowl, while the horizon sweeps up like a loosened spring. Then presently this illusion passes, and you see everything flat. There are no hills any more, nor villages; no towers nor steep descents, only a level surface, marked charmingly in color, sometimes in wonderful mosaics, and strangely in light and shade. At the height of two miles nothing is familiar; you might as well be looking at the moon, for all you can recognize. Roads become yellowish lines; rivers brownish lines (and the water vanishes); a mountain-range becomes a shaded strip, with less shade on one edge (where the sun is) than on the other; a forest becomes a patch of color; a town another patch. There is scarcely any difference between water and land, and you see to the bottom of a lake, so that the configuration of its bed in valley and hill are apparent through the color and the shading. This singular disappearance of water bodies, for it amounts to almost that, has an evident importance.
"I'll tell you what we did on Lake Ontario," said the professor, "as a result of observations I made there from a balloon. In sailing over the lake on one occasion I remarked a number of small shaded spots which puzzled me. I could not imagine what they were. Finally, with the help of powerful field-glasses, I made them out to be wrecks sunk at various depths, and I realized that Lake Ontario, and indeed all the great lakes, abound in vessels which have gone down during centuries and never been recovered. No one can estimate the treasure which lies there waiting for some one to reclaim it. And I saw that it is a perfectly simple matter to locate these wrecks from a balloon, and to prove this I organized a modest wrecking expedition, and indicated to the diver where he was to go down. Down he went at that point, and found the wreck I had seen, and we pumped good coal out of her by hundreds of tons. What I did then on a small scale might be done on a large scale by any one willing to undertake it."
Of course I asked the professor why it is that an aëronaut can see down into a lake better than, say, an observer in a boat, and he explained that there is a great gain in intensity of terrestrial illumination when the viewpoint is at a height, because the sun's rays converge toward the earth, the sun being so many times larger, and therefore (this is his theory) a man lifted above the earth gets many more solar rays reflected to him from a given area than he would get if nearer to that area. In a word, it is a matter of optics and angles, but, the professor declares, most assuredly a fact.
HOW THE EARTH LOOKS WHEN VIEWED FROM A HEIGHT OF ONE MILE.
(Photographed from a balloon.)
Never before these talks did I realize how busy an aëronaut is, how much there is to do in a balloon. Besides attending to valve-cords and ballast there is the barometer to keep your eyes on, for by it alone can you know your altitude. Around moves the needle slowly as you rise, slowly as you fall, one point for a thousand feet. Rising or falling, you know the worst or the best there. Sometimes the needle sticks, the barometer will not work, and you must cast overside pieces of tissue-paper to see by their rise or fall if you are going up or down. By your senses alone you cannot tell whether you are rising or falling, or your distance from the earth. That is most deceiving. Then you must have your watch ready to reckon your speed, so many thousand feet up or down in so many seconds, and your map spread out (nailed to a board, and that lashed fast), to tell where you are, and your compass out to fix the north and south points, for a balloon twists slowly all the time, twists one way going up and the other way coming down. Nobody knows just why this is, unless it be the unequal drawing of the seams as the fabric swells and shrinks.
"I always keep the mouth of my balloon within easy reach," said the professor, "and play with it as an engineer does with his throttle-valve. Sometimes I even tie it shut when I am sailing, but that is dangerous."
"Why dangerous?"