A great chain of volcanoes girdles the Pacific Ocean. The Andes in South America are studded with many volcanic summits, among them the loftiest volcanic mountains in the world: Cotopaxi in Ecuador is over 19,000 feet high. The Andes reached their present height only in the age of modern man.
Magma intruded into the rock and lifted it; in many places magma reached the surface, broke through vents, and built craters. Most of those volcanoes, however, are already extinct.
Central America abounds in volcanoes, most of them extinct or dormant; the highest, Orizaba in
Mexico, over 18,000 feet high, was active for the last time three centuries ago. In the United States few volcanoes are active, though many became extinct very recently, in the geological sense. Alaska, the Aleutian Islands, the Kamchatka Peninsula, and the Kurile Islands encircle the northern Pacific with a volcanic arc. The Japanese islands contain volcanoes by the score; most of them are extinct, some only recently so. Formosa, the Philippines, the so-called Volcano Islands - one of which is Iwo Jima - the Moluccas, northern New Zealand, the Sunda Archipelago - all are crowded with volcanoes, most of them only recently extinct. In the center of this chain are the Hawaiian Islands, with fifteen great mountainous volcanoes, all extinct or dormant except Mauna Loa and Kilauea, two of the largest volcanoes on earth. "How was that 30,000 foot cone built from the floor of the deep sea?" 1 When, in
1855, Mauna Loa erupted, the lava ran over the land at a velocity of forty miles an hour, faster than a swift horse. In 1883, when the volcanic island of Krakatoa in the Sunda Strait blew off, it sent a column of pumice and ashes over seventeen miles high; it raised tides 100 feet high that carried steamships miles inland and were felt on the eastern coast of Africa and the western coast of the Americas as far as Alaska; it created a noise that was heard in Ceylon, in the Philippines, and even in Japan over three thousand miles away. This would compare with an explosion in London heard in New York. When Bandai erupted in Japan in 1888, it cast up almost three billion tons of material and blew off one of its four peaks. But these delayed actions of single volcanoes look like child's play when compared with the forces that in past ages thrust up the Andes, spread the Deccan trap - the great lava flows, several thousand feet thick, that cover 250,000 square miles in India - built the lava dykes that cross South Africa, spread the Columbia Plateau in America, and laid the lava bed of the Pacific.
The Indian Ocean from Java, an island full of volcanoes, extinct, dormant, and active, to Kilimanjaro, an extinct volcano over 19,000 feet high in East Africa, is circled with volcanoes and its bottom is of
lava, with several volcanic isles in the middle of it. Along the Arabian coast of the Red Sea stretches a long chain of volcanoes; the numerous craters are all extinct, but it is not so long ago that they became inactive, the last eruptions having taken place in the year 1222 at Killis in northern Syria and in 1253 at Aden. 2
In the Mediterranean region Thera (Santorin), which exploded with unusual force about -1500, is still active or dormant; Etna on Sicily, a snow-capped volcano, Stromboli, and Vulcano are active. On the mainland of Europe, however, the only active volcano left is Vesuvius. In the past France and the British Isles saw extensive volcanic activity, and though this activity is ascribed to the Tertiary, some of "the cones, craters, and lava-streams [in France] ... stand out so fresh that they might almost be
supposed to have been erupted ony a few generations ago," in the words of Sir Archibald Geikie. 3
Iceland in the North Atlantic has 107 volcanoes on it and thousands of craters, large and small; none of the volcanoes is geologically ancient, but many of them are extinct. The island is covered with
coagulated lava, fissures, and crater formations. Iceland is one of the rare places where in modern times lava streams have been vomited from fissures in the earth without a crater having been formed.
From Iceland down the Atlantic, the Azores, the Canary Islands, the Cape Verde Islands, Ascension, and St. Helena are volcanic islands, some of them thrust up from the bottom of the ocean; their volcanic activity, like the activity of the many known volcanoes on the bottom of the Atlantic, has ceased.
In Patagonia volcanic eruptions have occurred down to fairly recent times, and the land between the Atlantic and the Andes is covered in many places with lava flows.
All in all only about four or five hundred volcanoes on earth are considered active or dormant, against a multiplicity of extinct cones. Yet only five or six hundred years ago many of the presently inactive volcanoes were still active. This points to very great activity at a time only a few thousand years ago. At the rate of extinction witnessed by modern man, the greater part of the still active volcanoes will become inactive in a matter of several centuries.
The cause of volcanic activity is supposed to be in movements and fractures of the outer crust of the earth, "however these may be brought about, a matter as yet by no means settled." The coincidence in time and place of mountain folding and volcano building is regarded as significant for the solution of the problem of the origin of volcanoes.
Seas of lava and crater formations cover the entire face of the moon. "No one who has observed the moon, even through a relatively small telescope, can forget this picture of tremendous catastrophe: a flood of molten lava that has engulfed ... and obliterated craters and mountain ridges in its path." 4
Whether the crater formations on the moon, some of which reach 150 miles in diameter, resulted from bombardment by enormous meteorites, or are extinct volcanoes, or, as I assumed in Worlds in
Collision, are the congealed effects of bubbling activity on the surface of the moon that became molten,
the face of the moon is indisputable proof of catastrophic events on a planetary scale. The theory of uniformity can be taught only on moonless nights.
As with the volcanic activity, the seismic shocks, judged by their effects, must have been of a very different order of magnitude in the past. "The earthquakes of the present day," writes Eduard Suess in his The Face of the Earth (Das Antlitz der Erde), "are certainly but faint reminiscences of those telluric movements to which the structure of almost every mountain range bears witness. Numerous examples of great mountain chains suggest by their structure ... episodal disturbances of such indescribable and overpowering violence, that the imagination refuses to follow the understanding ... " 5 Suess thought
that mountain building came to an end before the advent of man; but today we know that it lasted well into Recent time, and consequently man must have witnessed the great earthquakes that made the globe shudder.
When the Andes rose in South America, according to the description by R. T. Chamberlin, "Hundreds, if not thousands, of cubic miles of the body of the earth almost instantaneously heaved upward
earthquakes must have been by-products of the rise of the Sierras." 6
Again, we now know that the Sierras attained their present height in the age of man, in Recent time. And if we give credence to the records of earthquakes in the chronicles of the ancient East and in those of the classical age, we shall be amazed at the number of seismic shocks and tremors. One example is the Babylonian records on clay tablets stored in the library of Nineveh, excavated by Sir Henry Layard; another is the Roman records of a later age: in a single year during the Punic Wars (-217) fifty-seven earthquakes were reported in Rome. 7
From all this it is apparent that seismic activity on our planet subsided very quickly in intensity as well as in the number of occurrences; and this again would point to a stress or stresses that took place not so long ago: earthquakes are readjustments of the terrestrial strata, with accompanying relief from the stress.
The theory of Alexis Perrey, regularly quoted in textbooks, connects the occurrence of earthquakes in our time with the position of the nearest celestial body, the moon. Earth tremors occur more often when the moon is full or when the earth is between the sun and the moon; when the moon is new, or when it is between the sun and the earth; when the moon crosses the meridian of the afflicted locality; and when the moon is closest to the earth on its orbit. With the possible exception of the fourth case, the statistics for the last century appear to support Perrey's theory. But if this statistical theory is correct, then we have to look to the celestial sphere for the stresses that are relieved in earthquakes; and the farther in time from the stresses, the less numerous and less violent are the shocks.
Finally, a third natural phenomenon shows a definite downward curve. The number of comets visible to the unaided eye in recent centuries is only a small fraction of the number of cometary bodies that were observed in the historical past, in comparable periods of time. Whereas in our age about three comets are seen without the help of a telescope in the Northern Hemisphere in a century, in the days of imperial Rome, nineteen centuries ago, comets were so frequent that they were associated with many state events, such as the beginning of the rule of an emperor, his wars, his death. Often more than one comet was seen simultaneously. Some of the comets were spectacular and glowed even in the daytime. Approaching the sun, a comet emits a tail consisting of gases and dust particles. It is believed that these tails are wasted and that their material does not return to the head. A comet that recurs every seventy- six years, as Hailey's comet does, would have to grow and lose its tail about forty million times, if we take the usual figure for the age of the solar system, and such a wasting would have long ago reduced the comet to nothing.
In modern times, several comets of short period, or a period less than that of the Hailey comet, and thus subject to check by observatories, vanished and did not return when expected; the number of comets, at least of those closely associated with the solar system, becomes ever smaller.
According to a hypothesis offered by Swinne and referred to by H. Pettersson, "meteorites should be a relatively recent occurrence, limited to the last 25,000 years, and have been absent during preceding millions of years." 8
The rapid decrease in luminosity of periodical comets points to some unusual activity in the sky in the geologically recent past; in the careful estimate of the Russian astronomer S. K. Vsehsviatsky (1953), this unusual activity took place in historical times, only a few thousand years ago. 9
All three natural phenomena are on the wane. Volcanic activity is generally considered as connected with seismic activity; and the latter appears to be a response to a stress; and stress appears to have its origin in forces outside our earth.
_________________________________ 1 Daly: Our Mobile Earth, p. 91.
2 Monte: Arabien, Studien zur physikalischen und historischen Geographie des Landes, p. 12. 3 A. Geikie: The Ancient Volcanoes of Great Britain (1897), p. viii.
4 O. Struve, review of The Planets, Their Origin and Development, by H. Urey, in Scientific American, August 1952. 5 E. Suess: The Face of the Earth (1904), I, 17-18.
7 Pliny: Natural History (trans. Bostock and Rlley, 1855), II, 86. 8 Pettersson: Tellus (Quarterly Journal of Geophysics), I (1949), 4.
9 See reference to the work of S. K. Vsehsviatsky in the Supplement to this volume. _________________________________