f 



k 



XXX.l HEAT THE CAUSE OF CHANGE OF LEVEL. 



177 



That buildings should have been submerged, and afterwards 

 upheaved, without being entirely reduced to a heap of ruins 

 will appear no anomalj, when we recollect that, in the year 

 1819, when the delta of the Indus sank down, the houses 

 within the fort of Sindree subsided beneath the waves 

 without being overthrown. In like manner, in the year 1692, 

 the buildings around the harbour of Port Eoyal, in Jamaica, 

 descended suddenly to the depth of between 30 and 50 feet 



under the sea without falling, 

 land transported to a distance 



Even on small 

 mile 



tenements, like those near Mileto, in Calabria, were carried 

 entire. At Valparaiso buildings were left standing in 1822, 

 when their foundations, together with a long tract of the 

 Chilian coast, were permanently upraised to the height of 

 several feet. It is still more easy to conceive that an edifice 

 may escape falling during the upheaval or subsidence of land, 

 if the walls are supported on the exterior and interior with a 

 deposit like that which surrounded and filled to the height 

 of 10 or 11 feet the temple of Serapis all the time it was 

 sinking, and which enveloped it to more than twice that 

 height when it was rising again to its original level. 



We can scarcely avoid the conclusion, as Mr. Babbage has 

 hinted, ' that the action of heat is in some way or other the 

 cause of the phenomena of the change of level of the temple. 

 Its own hot spring, its immediate contiguity to the Solfatara 



Monte Nuo 



Nero CN' 



of Baise ; the boiling springs and ancient volcanos of Ischia 



multitude 



most 



And 



when we reflect on the dates of the principal oscillations of 

 level, and the volcanic history of the country before described 

 (Chapter XXIV.), we seem to discover a connection between 

 each era of upheaval and a local development of volcanic 

 heat, and agam between each era of depression and the local 



■ ■III /_■ L_1 /■ /^^i/^ j^^ j^^ .F^_^l I '^ ^ m m ^ 



dormant 



causes. 

 many \ 



ihus, for example, before the Christian era, when so 



VOL, II. 



* Quart. Journ. Geo!. Soc. 1847, vol. iii. p. 203. 



