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fractures and meridional splits, from which water is sometimes 

 seen bursting out. 



With regard to lands being gradually elevated and depressed 

 unaccompanied by earthquakes, Professor Lyell has abundantly 

 proved in his • Principles of Geology/ and has also made very 

 lucid observations on this part of our subject. The coast of 

 Brazil is subject to changes like the Chilian coast, although 

 earthquakes are seldom felt there ; but we have more satisfac- 

 tory proofs in the gradual sinking of the western coast of Green- 

 land, and the equally slow and gradual movement taking place 

 throughout a large part of Sweden and Finland, and a number 

 of other parts in the northern hemisphere, where earthquakes 

 are seldom felt. How much more satisfactory and consistent with 

 the ordinary laws of nature is it to regard these grand opera- 

 tions as regular and necessary effects of great and general causes 

 of the action of terrestrial magnetism, than to suppose them as 

 resulting from series of convulsions and catastrophes, regulated 

 by no laws, and reducible to no fixed principles ! 



In making comparisons between the ancient latitudes of twelve 

 places in South America with recent observations, we find an 

 average difference amounting to about twenty minutes in favour 

 of a more northerly position. Humboldt took the latitude of 

 Mariquita about forty years ago, and made it 5° 13' 0" north. 

 The author continued a series of observations in the same neigh- 

 bourhood, and connected the above point with others by trigo- 

 nometrical measurements : the latitude of the same spot is now 

 5° 25' 30". The observations were not confined to a star or the 

 sun alone, but taken from various celestial points, with their 

 complementary angles, by fixed theodolites, a sextant, and a re- 

 peating circle. Similar observations were made at other points. 

 It is therefore concluded that South America is not only subject 

 to vertical undulations, but also to a horizontal movement en 

 masse northward, amounting to at least ten seconds per annum. 

 However, w T e shall not dwell on this fact, but shall refer to other 

 evidences, as being more substantial and satisfactory proofs of 

 the northerly movement of the earth's surface. It is the neces- 

 sary consequence of the action of the polar force, which may be 

 proved by an artificial globe having an electro-magnetic axis, 

 placed horizontally in a fluid containing salts : the masses formed 



