The Man Who Rocked the Earth/Chapter 4
Free translation of the Official Report of the Imperial Commission of the Berlin Academy of Science to the Imperial Commissioners of the German Federated States:
The unprecedented cosmic phenomena which occurred on the 22d and 27th days of the month of July, and which were felt over the entire surface of the globe, have left a permanent effect of such magnitude on the position of the earth's axis in space and the duration of the period of the rotation, that it is impossible to predict at the present time the ultimate changes or modifications in the climatic conditions which may follow. This commission has considered most carefully the possible causes that may have been responsible for this catastrophe—(Weltunfall)—and by eliminating every hypothesis that was incapable of explaining all of the various disturbances, is now in a position to present two theories, either one of which appears to be capable of explaining the recent disturbances.
The phenomena in question may be briefly summarized as follows;
1. The Yellow Aurora. In Northern Europe this appeared suddenly on the night of July 22d as a broad, faint sheaf—(Lichtbündel)—of clear yellow light in the western sky. Reports from America show that at Washington it appeared in the north as a narrow shaft of light, inclined at an angle of about thirty degrees with the horizon, and shooting off to the east. Near the horizon it was extremely brilliant, and the spectroscope showed that the light was due to glowing helium gas.
The Potsdam Observatory reported that the presence of sodium has been detected in the aurora; but this appears to have been a mistake due to the faintness of the light and the circumstance that no comparison spectrum was impressed on the plate. On the photograph made at the Washington Observatory the helium line is certain, as a second exposure was made with a sodium flame; and the two lines are shown distinctly separated.
2. The Negative Acceleration. This phenomenon was observed to a greater or less extent all over the globe. It was especially marked near the equator; but in Northern Europe it was noted by only a few observers, though many clocks were stopped and other instruments deranged. There appears to be no doubt that a force of terrific magnitude was applied in a tangential direction to the surface of the earth, in such a direction as to oppose its axial rotation, with the effect that the surface velocity was diminished by about one part in three hundred, resulting in a lengthening of the day by five minutes, thirteen and a half seconds.
The application of this brake—(Bremsekraft), as we may term it—caused acceleration phenomena to manifest themselves precisely as on a railroad train when being brought to a stop. The change in the surface speed of the earth at the equator has amounted to about 6.4 kilometres an hour; and various observations show that this change of velocity was brought about by the operation of the unknown force for a period of time of less than three minutes. The negative acceleration thus represented would certainly be too small to produce any marked physiological sensations, and yet the reports from various places indicate that they were certainly observed. The sensations felt are usually described as similar to those experienced in a moving automobile when the brake is very gently applied.
Moreover, certain destructive actions are reported from localities near the equator—chimneys fell and tall buildings swayed; while from New York comes the report that the obelisk in Central Park was thrown from its pedestal. It appears that these effects were due to the circumstance that the alteration of velocity was propagated through the earth as a wave similar to an earthquake wave, and that the effects were cumulative at certain points—a theory that is substantiated by reports that at certain localities, even near the equator, no effects were noted.
3. Tidal Waves. These were observed everywhere and were very destructive in many places. In the Panama Canal, which is near the equator and which runs nearly east and west, the sweep of the water was so great that it flowed over the Gatun Lock. On the eastern coasts of the various continents there was a recession of the sea, the fall of the tide being from three to five metres below the low-water mark. On the western coasts there was a corresponding rise, which in some cases reached a level of over twelve metres.
That the tidal phenomena were not more marked and more destructive is a matter of great surprise, and has been considered as evidence that the retarding force was not applied at a single spot on the earth's surface, but was a distributed force, which acted on the water as well as on the land, though to a less extent. It is difficult, however, to conceive of a force capable of acting in such a way; and Björnson's theory of the magnetic vortex in the ether has been rejected by this commission.
4. Atmospheric Disturbances. Some time after the appearance of the yellow aurora a sudden rise in atmospheric pressure, followed by a gradual fall considerably below the normal pressure, was recorded over the entire surface of the globe. Calculations based on the time of arrival of this disturbance at widely separated points show that it proceeded with the velocity of sound from a point situated probably in Northern Labrador. The maximum rise of pressure recorded was registered at Halifax, the self-recording barographs showing that the pressure rose over six centimetres in less than five minutes.
5. Shift in Direction of the Earth's Axis. The axis of the earth has been shifted in space by the disturbance and now points almost exactly toward the double star Delta Ursæ Minoris. This change appears to have resulted from the circumstance that the force was applied to the surface of the globe in a direction not quite parallel to the direction of rotation, the result being the development of a new axis and a shift in the positions of the poles, which it will now be necessary to rediscover.
It appears that these most remarkable cosmic phenomena can be explained in either of two ways: they may have resulted from an explosive or volcanic discharge from the surface of the earth, or from the oblique impact of a meteoric stream moving at a very high velocity. It seems unlikely that sufficient energy to bring about the observed changes could have been developed by a volcanic disturbance of the ordinary type; but if radioactive forces are allowed to come into play the amount of energy available is practically unlimited.
It is difficult, however, to conceive of any way in which a sudden liberation of atomic energy could have been brought about by any terrestrial agency; so that the first theory, though able to account for the facts, seems to be the less tenable of the two. The meteoric theory offers no especial difficulty. The energy delivered by a comparatively small mass of finely divided matter, moving at a velocity of several hundred kilometres a second—and such a velocity is by no means unknown—would be amply sufficient to alter the velocity of rotation by the small amount observed.
Moreover, the impact of such a meteoric stream may have developed a temperature sufficiently high to bring about radioactive changes, the effect of which would be to expel helium and other disintegration products at cathode-ray velocity—(Kathoden-Strahlen-Fortpflanzung-Geschwindigkeit)—from the surface of the earth; and the recoil exerted by this expulsion would add itself to the force of the meteoric impact.
The presence of helium makes this latter hypothesis not altogether improbable, while the atmospheric wave of pressure would result at once from the disruption of the air by the passage of the meteor stream through it. Exploration of the region in which it seems probable that the disturbance took place will undoubtedly furnish the data necessary for the complete solution of the problem." [Pp. 17-19.]