94 Charles Darwin. 



The young naturalist made a careful examination 

 of Concepcion. He found that one set of walls in 

 the city extended south-west by west, another north- 

 west by north, and that the former stood the shock 

 by far the best, showing in his estimation that the 

 undulations came from the north-west, from which 

 direction subterranean noises and rumblings were 

 heard. The fissures in the earth generally extended 

 south-east by north-west, corresponding to some de- 

 gree with the undulations. The disturbance in the 

 ocean was found to be of a varied nature. With the 

 first shock the water moved up gently, then with- 

 drew to the former position ; almost immediately it 

 began to retreat seaward, as if to collect itself, and 

 then came in again with a rush upon the shore. 

 The first movement Darwin judged to be the im- 

 mediate result of the earthquake affecting differently 

 a fluid and a solid, the levels being disarranged. 

 He considered the permanent elevation of the land 

 perhaps the most remarkable phenomenon, as about 

 Concepcion it was elevated two or three feet. At 

 the island of Santa Maria Captain Fitz-Roy found 

 beds of putrid mussels ten feet above high water, 

 projected there by the earthquake ; and as Darwin 

 came across beds of shells at an elevation of a thou- 

 sand feet, he assumed that it had been effected by a 

 series of small risings. To give a realistic idea of 

 the area of this disturbance, Darwin says : 



" It will give a better idea of the scale of these 

 phenomena if (as in the case of the glaciers) we sup- 

 pose them to have taken place at corresponding dis- 

 tances in Europe : then would the land from the 





