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POPULAR SCIENCE MONTHLY 



THE PROGRESS OF SCIENCE. 



THE EARTHQUAKE ON THE CALI- 

 FORNIA COAST 



It is too late to describe here the 

 appalling disaster that has overtaken 

 San Francisco and the neighboring re- 

 gions and too soon to attempt to pre- 

 sent a scientific survey of the causes 

 leading to the catastrophe and the 

 precautions that should be taken to 

 avoid its recurrence. We can but add 

 one more expression of the universal 

 sympathy and a further appreciation 

 of the undaunted courage which leads 

 men to assert their supremacy even in 

 the face of the most terrible exhibition 

 of the powers of nature. 



The progress of science and the con- 

 ditions of modern civilization have 

 been the chief causes of the calamity; 

 yet we may confidently look to the 

 same factors to prevent its recurrence. 

 Earthquakes occur daily, and a shock 

 such as that of April 18 would have 

 done but small damage to a farming 

 community. The trouble was due, on 

 the one hand, to large piles of masonry 

 or fiimsy brickwork unsuited to resist 

 vibrations, and, on the other, to the 

 conflagation. The live electric wires, 

 the methods of heating, lighting and 

 applying power, the dependence of a 

 modern city on its fire department 

 and a supply of water through mains, 

 not only explain the San Francisco fire, 

 but made it almost inevitable. On 

 the other hand, the steel frames and 

 concrete reenforced with steel wires, 

 proved themselves, as had been fore- 

 seen, well fitted to resist destruction. 

 The only trouble was the shaking off 

 of the stones and bricks' and the in- 

 flammable contents. If it were not for 

 the est liet ic effects, such buildings might 

 be covered with metal sheathing and be 



made fire-proof within as well as with- 

 out. They would then be earthquake- 

 proof — at least for such shocks as 

 are known to have occurred — and would 

 be as effective as open spaces in stop- 

 ping the spread of a conflagation. San 

 Francisco will take all needful pre- 

 cautions. Whether cities less likely to 

 suffer should do so is more doubtful. 

 The effects of an earthquake in New 

 York City would be appalling. The 

 people would rush into the streets, too 

 narrow to hold them, while the stones 

 would be shaken down on their heads, 

 the conditions being similar to those of 

 a vast theater fire. But more lives 

 are needlessly sacrificed in New York 

 City each month than have been lost 

 in the California disaster, and more 

 money is wasted each year than is 

 needed to rebuild San Francisco. 



The causes of earthquakes are some- 

 what obscure and are doubtless of dif- 

 ferent kinds. They are part of the 

 vast terrestrial phenomena which have 

 lifted the continents and the mountain 

 ranges. The main stresses may be 

 due to contraction of the crust of the 

 earth or to changes in its shape, while 

 the proximate causes are the local 

 geological formations. The conditions 

 at San Francisco are fairly well under- 

 stood. There is a fault in the pen- 

 insula along the Portohi Valley, where 

 for about forty miles the rocks on one 

 side have at some time sunk two thou- 

 sand feet. At the time of the recent 

 earthquake, the land on the west side 

 of the fault was forced northward from 

 three to six feet, and the violent dis- 

 location accounts for the shock. Mr. 

 G. K. Gilbert has been instructed by 

 the U. S. Geological Survey to make 

 a thorough study of the causes, and we 



