170 EAETHQUAKES. 



would have made itself appreciable over the surface of the 

 whole of our globe. At places on the South American 

 coast, it has been stated that the height of the waves varied 

 from twenty to eighty feet. At the Samoa Islands the 

 heights varied from six to twelve feet. In New Zealand 

 the sea rose and fell from three to twenty feet. In Australia 

 the heights to which the water oscillated were similar to 

 those observed in New Zealand. In Japan it rose and fell 

 from five to ten feet. In this latter country, the phenomena 

 of sea waves which follow a destructive earthquake on the 

 South American coast are so well known that old residents 

 have written to the local papers announcing the probability 

 of such occurrences having taken place some twenty-five 

 hours previously in South America. In this way news of 

 great calamities has been anticipated, details of which only 

 arrived some weeks subsequently. Just as the destructive 

 earthquakes of South America have announced themselves 

 in Japan, in a like manner the destructive earthquakes of 

 Japan have announced themselves upon the tide gauges 

 of California. Similarly, but not so frequently, disturbances 

 shake the other oceans of the world. 



For example, the great earthquake of Lisbon propagated 

 waves to the coasts of America, taking on their journey 

 nine and a half hours. 



Sea ^uaves without earthquakes. — Sometimes we get 

 great sea waves like abnormal tides occurring without 

 any account of contemporaneous earthquakes. Although 

 earthquakes have not been recorded, these ill understood 

 phenomena are usually attributed to such movements. 



Several examples of these are given by Mallet. Thus, 

 at 10 A.M. on March 2, 1856, the sea rose and fell for a 

 considerable distance at many places on the coast of York- 

 shire. At Whitby, the tide was described ebbing and 

 flowing six times per hour, and this to such a distance 



