506 



elevation of the whole coast of the Pacific from Peru to Terra del 

 Fuego. Beds of shells were traced by him at various heights above 

 the sea, some a few yards, others 500 or even 1300 feet high, the 

 shells being in a more advanced state of decomposition in propor- 

 tion to their elevation. Mr. Darwin also shows that parallel ter- 

 races such as those of Coquimbo, described by Captain Basil Hall 

 and others, which rise to the height of 300 feet and more, are of 

 marine origin, being sometimes covered with sea-shells, and they 

 indicate successive elevations. There are also grounds for believing 

 that the modern upheaval of land has proceeded not only by sud- 

 den starts during convulsions of the earth, but also by insensible 

 degrees in the intervals between earthquakes, as is now admitted to 

 be the case in parts of Norway and Sweden. 



This gradual and insensible rising is supposed to affect, not only 

 the region of the Andes, but also the opposite or eastern coast of 

 South America, where earthquakes are never experienced : for 

 the Pampas of Buenos Ayres bear marks of having risen to their 

 present height during a comparatively modern period, while the 

 coast line of the Pacific, or the region of earthquakes and volcanic 

 eruptions, has been the theatre of more violent movements. 



It is curious to reflect that if in one portion of a large area of tlie 

 earth's surface a rise of land takes place at the rate of a few inches 

 in a century, as around Stockholm, while in another portion of the 

 same area land is uplifted about a yard during an equal period, there 

 will be caused, if sufficient time be allowed, a group or cliain of 

 lofty mountains in one place, and in the other a low country like 

 the Pampas of South America. 



Evidence of a sinking down of land, whether sudden or gradual, 

 is usually more difficult to obtain than the signs of upheaval. I shall 

 therefore mention some facts which have been lately communicated 

 to me by Professor Nilsson, from which it appears that Scania, or 

 the southernmost part of Sweden, has been slowly subsiding for se- 

 veral centuries, in the same manner as was lately shown to be the 

 case with part of Greenland. In the first place there are no elevated 

 beds of recent marine shells in Scania, like those near Stockholm and 

 further to the north. Linnaeus, with a view of ascertaining whether 

 the waters of the Baltic were retiring from the Scanian shore, 

 measured in 1749 the distance between the sea and a large stone 



