264 Notices and Extracts from the Minutes of the Geological Society, 



on Chili, to the statements contained in which, neither he nor his friends could 

 subscribe. 



Mr. Cuming's pursuit of conchology and natural history generally, caused 

 him to visit frequently the rocks and inlets with which the northern and 

 southern parts of the bay abound ; but though the rocks were covered with 

 Puci, Patellae, Chitons, Balani, &c., yet he never perceived the least difference 

 in their appearance from the date of his arrival to his finally quitting Valpa- 

 raiso. He mentions particularly, as points which he often examined, the 

 Caleta, the Quebrada de Dios, and the Cruz de Reyes. He also never found 

 the least trace of the above productions, except in situations covered by the 

 tide. 



After the earthquake, Mr. Cuming resided in a house in the Arsenal, where 

 the spring tides came up to the same mark as they did previously to that event. 

 He refers especially to the tides of 1822 and J823. 



Another circumstance which convinced Mr. Cuming that no change of 

 level had taken place, was the existence of a small detached rock opposite the 

 Estanco, half-way between the Custom-house and the Market-place, and 

 about fifty yards from the walls at half tide. From this rock he had often taken 

 Concholepas Peruviana, previously to the earthquake, and subsequently it 

 retained the same position. 



The vessels occupied the same anchorage as they did before November 

 J 822 ; and nautical men affirmed that there was not the least difference in the 

 depth of the water in any part of the bay. 



The opinion that a change had taken place in the relative level of land and 

 sea, Mr. Cuming conceives, originated in the accumulation of detritus at points 

 where the tide Howed anterior to the earthquake, and on which houses and 

 even small streets have been since erected. Though these accumulations ap- 

 pear to have been forming between 50 and 80 years, yet they were small 

 previously to the violent rains in June 1827, which brought down into the 

 bay the loose granitic soil of the hills and the ravines. This detritus has since 

 been thrown up by the tides, and formed into a firm open space exceeding 

 250 feet in breadth, on which the buildings have been erected. In front of 

 the Custom-house, however, the accumulations were trifling, and the landing 

 place remained in the same state as in 1822. 



The quantity of matter thus carried into the bay has not affected the an- 

 chorage, and Mr. Cuming, when dredging within two hundred yards of low- 

 water mark, never found a grain of decomposed granite, or any kind of recent 

 soil, but fine sandy mud, well stocked with several species of shells of mature 

 grouth. 



