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tonio, near the northern point of that river, are large quarries of 

 shells. Between this point and Valparaiso in the ravine, Quebrada 

 Onda, the remains of a species of shell common on the coast, were 

 noticed by the author. Along the bold granitic coast south of the pro- 

 montory which forms the bay of Valparaiso, are numerous level and 

 horizontal beds of shells, constituting an almost continuous band, 

 elevated from 60 to 230 feet above the level of the sea. The shells 

 are brittle, but of various kinds, and are all similar and in similar pro- 

 portional numbers to those on the beach. They are mingled with 

 some earth, though packed closely together, and overlie a partially 

 consolidated breccia of granitic fragments which rests on the solid 

 rock. After a careful examination of these deposits, first by himself, 

 and afterwards with Mr. Alison, guarded by a recent inspection of 

 the heaps of shells accumulated by the natives in Tierra del Fuego, 

 Mr. Darwin was convinced that the shelly beds near Valparaiso, were 

 formed when the sea occupied a different level. The following are 

 the principal circumstances which lead to this conviction. The great 

 number of the shells forming extensive, horizontal beds, whereas the 

 heaps in Tierra del Fuego coUectedby the inhabitants, always retain a 

 conical figure: their position, at the extremities of headlands inac- 

 cessible from the sea, and unfit for strongholds, being without fresh 

 water: the large proportional number of extremely small shells : and 

 lastly, their brittle and decayed condition, the state of decomposition 

 having an evident relation to the comparative heights at which the 

 shells were lying. Comminuted shells were noticed by Mr. Darwin at 

 the heights of 560 and 1300 feet, but the evidence of their having 

 been part of a beach was not convincing. 



At San Lorenzo in the bay of Callao, Mr. Darwin traced a similar 

 process of decay from perfect shells in the lowest beds to a mere 

 layer of calcareous powder in the highest. This phenomenon, he adds, 

 can be observed only in countries where rain never falls. 



On the north side of the bay of Valparaiso, near the Vina del Mar, 

 is an abundance of elevated shells. Mr. Alison, by climbing a point 

 of rock about fourteen feet above high water, and removing the dung 

 of sea fowls, discovered Balani adhering to the stone. 



With respect to the historical evidence of the earthquake of 1822, 

 Mr. Darwin says that he met with no intelligent person who doubted 

 the rise of the land, or with any of the lower order who doubted that 

 the sea had fallen. He mentions also the altered position of the 

 wreck and of the rock in the bay ; and from a part of the fort being 

 invisiblefroma point on the land before the earthquake, but visibleafter- 

 wards, he infers that the movement of the land was unequal*. A 

 further proof of change, obtained for the author by Mr. Alison, is 

 shown by the remains of a sea-wall built in 1680, and over which, 

 up to 1817, the sea broke during the northerly gales. Mr. John 

 Martin, a ship carpenter of Valparaiso, remembers walking in 1819 

 on the beach at the foot of this wall, and he has been frequently 

 obliged to climb up to the street to avoid the sea. This wall is now 

 separated from the bay by two rows of houses, but a portion of what 

 * See note * in the preceding page. 



