"Sit down. Take your time," said Von Helmuth, looking out and up at a monoplane descending toward the landing in slowly lessening spirals.
"You see, your Excellency," explained Von Schwenitz, "the data are fragmentary, but I used three methods, each checking the others."
"The first?" shot back the general. The monoplane had landed safely.
"I compared the records of all the seismographs that had registered the earthquake wave attendant on the electrical discharges accompanying the great yellow auroras of July. These shocks had been felt all over the globe, and I secured reports from Java, New Guinea, Lima, Tucson, Greenwich, Algeria, and Moscow. These showed the wave had originated somewhere in Eastern Labrador."
"Yes, yes. Go on!" ordered the general.
"In the second place, the violent magnetic storms produced by the helium aurora appear to have left their mark each time upon the earth in a permanent, if slight, deflection of the compass needle. The earth's normal magnetic field seems to have had superimposed upon it a new field comprised of lines of force nearly parallel to the equator. My computations show that these great circles of magnetism centre at approximately the same point in Labrador as that indicated by the seismographs—about fifty-five degrees north and seventy-five degrees west."
The general seemed struck with this.
"Permanent deflection, you say!" he ejaculated.
"Yes, apparently permanent. Finally the barometer records told the same story, although in less precise form. A compressional wave of air had been started in the far north and had spread out over the earth with the velocity of sound. Though the barographs themselves gave no indication whence this wave had come, the variation in its intensity at different meteorological observatories could be accounted for by the law of inverse squares on the supposition that the explosion which started the wave had occurred at fifty-five degrees north, seventy-five degrees west."
The professor paused and wiped his glasses. With a roar a Taube slid off the landing stage, shot over toward the hangars, and soared upward.