Mr Smith on (he Changes of the Level of the Sea, 385 



had become stationary at its present level. I am inclined to 

 think that this has been the case on the west coast of Ireland ; 

 in the counties of Clare and Kerry I observed no stratified beds 

 above the diluvium, and, on the shores of the Shannon which 

 divides them, no terraces except those forming at present. 

 These facts, however, seem rather to prove different periods of 

 diluvial agency than of elevation and depression. 



The changes of level must have taken place anterior to the 

 historic period, which in this country dates from the invasion of 

 the Romans. Diodorus Siculus,* who wrote during the reign 

 of Augustus, describes St Michaers Mount in Cornwall under 

 the name Ixng, as an island connected with the mainland by a 

 space covered every tide, but dry at low water, — a description 

 Avhich would apply accurately at the present day. In Scotland, 

 the Roman wall, which crosses the island from sea to sea, has 

 evidently been formed at botli ends with reference to the pre- 

 sent level. The same observation applies to British tumuli and 

 vitrified forts, which are perhaps of still greater antiquity. It 

 is, therefore, highly probable, that no changes of level have 

 taken place since the British islands have been tenanted by 

 man. 



We have ample proof that traces of these changes occur in 

 every part of our coasts. In England, the observations of Messrs 

 Phillips, -|- Rose, J Ilobberds, || Sedgwick, § &c., on the east 

 coast ; Messrs Mantell, H De la Beche,** Sedgwick, and Mur- 

 chison,tt on the south ; and Sir Philip Egerton, Messrs Mur- 

 chison, Gilbertson, &c.,tt on the west, shew, that in all parts 

 of the English coasts they are to be met with. In Scotland, in 

 addition to the Notices, in the Wernerian Memoirs, already ad- 

 verted to, the Statistical Account abounds in direct or inciden- 

 tal notices of similar phenomena. My own observations, and 

 those of every well qualified observer, confirm their universality 

 in this part of the island. 



* Diod. Sic. Book v. Quoted in Thomson's Outlines of Mineralogy and 

 Geology, vol. ii. p. 45. 



t Geol. of Yorkshire, vol. i. p. 23. t Phil. Mag. Jan. 183G, p. 30. 



11 Phil. Mag. March 1827, p. 223, &c. 



§ Geol. Soc. Proceedings, vol. i. p. 409. 



*l Geol. of Sussex, 285. Geol. Proc. ii. 203. •* Geol. Manual, 140. 



ft Proc. Geol. Soc. Dec. 1836. 



