1 



148 



EAETHQUAKE OF LISBON. 



[Ch. XXX. 



beyond the reacli of falling ruins ; but suddenly the quay 

 sank down with all the people on it^ and not one of the dead 



number 



bodies ever floated to the surface. A great 

 and small vessels anchored near it, all full of people, were 

 swallowed up, as in a whirlpool."^ No fragments of these 

 wrecks ever rose again to the surface, and the water in the 

 place where the quay had stood is stated, in many accounts, 



, - Whitehurst 



to be 100 fathoms. t 



Circumstantial as are the contemporary narratives, I was 

 informed by Mr. F. Freeman, in 1841, that no part of the 

 Tagus was then more than 30 feet deep at high tide, and an 

 examination of the position of the new quay, and the 

 memorials preserved of the time and manner in which it was 

 built, render the statement of so great a subsidence in 1755 

 quite unintelligible. Perhaps a deep narrow chasm, such as 

 was before described in Calabria (p. 125), opened and closed 

 again in the bed of the Tagus, after swallowing up some 

 incumbent buildings and vessels. We have already seen 

 that such openings may collapse after the shock suddenly, or 

 in places where the strata are of soft and yielding materials, 

 very gradually. According to the observations made at 

 Lisbon, in 1837, by Mr. Sharpe, the destroying effects of this 

 earthquake were confined to the tertiary strata, and were 

 most violent on the blue clay, on which the lower part of the 

 city is constructed. Not a building, he says, on the secondary 



limestone or the basalt was injured. J 



The area over which this convulsion extended is very 

 remarkable. It has been computed, says Humboldt §, that 

 on November 1, 1755, a portion of the earth's surface four 

 times greater than the extent of Europe was simultaneously 

 shaken. The shock was felt in the Alps, and on the coast of 

 Sweden, in small inland lakes on the shores of the Baltic, in 

 Thuringia, in the flat country of northern Germany, and in 



^ Eer. C. Davy's Letters, vol. ii. 

 Letter ii. p. 12, who was at Lisbon at 

 the time, and ascertained that the Loats 

 and vessels said to have been swallowed 

 were missing 



t On the Formation of the Earth, 



p. 55. 



X Geol. Soc. Proceedings, No. ^^, 



p. 36. 1838. 



Cosmos, vol. i. 



r 



f 



( 



( 



\ 





( 



if 



of 



Bl 









f8 



been 



them 

 SI 



of a: 



same 



oftb 

 thoii{ 



lead, 

 Deni 



mom 

 stmd 

 and f 

 ship, 



aeoi 

 I^rpe 



lates, 



AtL( 



suhsi 



K 



posit 

 given 



^ 

 H. 



V 



H 

 H, 



