1824.] Geological Society. 461 



formed a vast sea ; but their height, in some places 700 feet 

 above the Black Sea, and 1000 feet above the Caspian, pre- 

 cludes the possibility of this. 



The author, after enumerating and describing the series of 

 the above-mentioned beds, and their accompanying fossils, 

 concludes with remarks on the probable extension of the Cas- 

 pian Sea, and the sea of Aral, and their connexion with the 

 Black Sea by means of the low steppe. 



A letter from Mrs. Maria Graham to Henry Warburton, Esq. 

 VPGS. was read, giving an account of the effects of the Earth- 

 quakes which visited the coast of Chili in 1822 and 1823. 



The first shock by which the towns of Valparaiso, Melipil'.a 

 and Quillota were nearly destroyed, was felt at a quarter past 

 1 1 o'clock on the evening of Tuesday the 19th of November, 

 1822; and from this time continual shocks were felt daily until 

 the 18th of January, when the authoress ceased to reside in 

 Chili. These shocks are. said not to have terminated wholly so 

 late as September last. The sensation experienced during the 

 more violent shocks was that of the earth being suddenly heaved 

 up in a direction from N. to S. and then falling down again, a 

 transverse motion being now and then felt. On the 1 9th of 

 November a general tremour was felt, and a sound heard like 

 that of vapour bursting out, similar to the tremour and sound 

 which the authoress observed while standing on the cone of 

 Vesuvius during the jets of fire at the eruption of 1818. In all 

 the alluvial valleys in the neighbourhood of Quintero, 30 miles 

 N. of Valparaiso, quantities of water and sand were forced up, 

 which covered the plain of Vina a la Mar with cones or hillocks 

 four feet high. 



The promontory of Quintero, consisting of granite covered 

 by sandy soil, was cracked in various directions down to the 

 sea ; and the cracks occasioned by the earthquake in the gra- 

 nite on the beach were parallel to the more ancient rents in the 

 same rock. 



On the morning of the 20th, after the first earthquake the 

 whole line of coast from N. to S. to the distance of 100 miles 

 was found to have been raised out of the sea; the elevation at 

 Quintero being about four feet, that at Valparaiso about three 

 feet, beds of oysters and muscles, adhering to the rock on 

 which they grew, being seen lying dry on the beach. 



Similar lines of beach with shells are found parallel to the 

 coast to the height of 50 feet above the sea, which probably 

 have been occasioned by earthquakes which have in former 

 years visited Chili. 



The earthquake of the 19th was felt along the coast to the 

 distance of 1400 miles at least. 



March 19, 1824. — A paper entitled " Sketch of the Geology 

 of New South Wales and Van Diemeu's Laud," by the Rev. T. 

 H. Scott, was read in part. 



