There is one very remarkable circumstance in regard to all this activity. All the places mentioned—Formosa, Southern Italy, Caucasia and the Canary Islands—lie within a belt bounded by lines a little north of the fortieth parallel and a little south of the thirtieth parallel. San Francisco is just south of the fortieth parallel, while Naples is just north of it. The latitude of Calabria, where the terrible earthquakes occurred last year, is the same as that of the territory affected by yesterday’s earthquake in the United States.
There is another coincidence, which may be only a coincidence, but which is also suggestive. The last previous great eruption of Vesuvius was in 1872, and the same year saw the last previous earthquake in California which caused loss of life.
Camille Flammarion expressed the opinion that the earthquake at San Francisco and the eruption at Vesuvius are directly connected. He also sees a connection between the renewed activity of Popocatepetl, Mexico’s well-known volcano, and the disturbance on the Western coast. He says that, though the surface of the earth is apparently calm, “there is no real equilibrium in the strata of the earth,” and that the extreme lateral pressure which is still forming mountains and volcanoes along the Western coast brought about an explosion of gases and the movement of superheated steam several miles below San Francisco, resulting in an earthquake.
Another theory is that the earth in revolving is flattening at the poles and swelling at the equator, and the strata beneath the surface are shifting and sliding in an effort to accommodate themselves to the new position. Other scientists scout this idea, saying that earthquakes are not caused by the adjustment of the surface of the earth, but by jar and strain as the earth makes an effort to regain its true axis.
As regards the possible connection between volcanoes and earthquakes, it is known that a violent earthquake, whose shocks lasted several days, accompanied the eruption of Vesuvius in the year 79, when Pompeii and Herculaneum were destroyed. In 1755 thousands upon thousands of people lost their lives in the memorable earthquake at Lisbon, in Portugal. At the same time the warm springs of Teplitz, Bohemia, disappeared, later spouting forth again. In the same year an Iceland volcano broke forth, followed by an uprising and subsidence of the water of Loch Lomond in Scotland. The eruption of Vesuvius in 1872 was followed soon after by a serious earthquake in California.
Coming to the present year, it is noticed that the earthquake in the island of Formosa, in which 1,000 people lost their lives, was followed by the eruption of Vesuvius on April 8. Soon after came the second great shock in Formosa, in which there was an even greater loss of life.
Later there were two earthquake shocks in Caucasia. At the same time the news of this appeared there was a report of renewed activity on the part of a volcano in the Canary Isles, which had long been dormant. In the United States two volcanoes which have been regarded as extinct for more than a century—Mount Tacoma and Mount Rainier—began to emit smoke. In regard to Tacoma, Dr. W. J. Holland, head of the Carnegie Institute at Pittsburg, says: “There is no doubt that there has been a breakdown and shifting of strata, perhaps at a very great depth, in the region of San Francisco. There certainly is great connection between this earthquake and recent private reports which have come to me of intense volcanic activity on the part of Mount Tacoma.”
On the other hand, leading scientists contend that these instances are mere coincidences. “If there is any connection between Vesuvius and the Caucasus and Canary Isles earthquakes other places would have suffered too; New York, for instance, is on the same parallel,” says Prof. J. F. Kemp, of Columbia University.
Although each of these scientists has the most absolute faith in his theory, he really knows no more about the facts than any boy on the street. No one has ever descended into the interior of the earth and investigated the heart of a volcano but Jules Verne, and he only in his mind. What is needed now is exact information. The San Francisco catastrophe will teach many lessons, and among them the necessity for the close study of both volcanoes and earthquakes. There is no reason why earthquakes and other internal disturbances cannot be observed just as closely as the weather. In fact, it is entirely probable that the time will come when a seismological bureau will exist for the study of earthquakes, just as there is a Weather Bureau for observation of the weather, and it will be the business of its officials to prophesy and warn of approaching internal disturbances of the earth, just as the weather men announce the approach of bad weather. Government observation stations will be established, exact records will be kept, and in the course of time we shall learn exactly what earthquakes are and what are their causes.
Among other lessons that the disaster has taught is that the much-maligned skyscraper is about the safest building there is. Its steel-cage structure, with steel rods binding the stone to its wall, has stood the test and has not been found wanting. Of all the mighty buildings in San Francisco those of the most modern structure alone survived. Their safety in the midst of collapsing buildings of mortar and brick argues well for like structures in other cities.