Dr Hibbert's Observations on Vitrified Forts. 307 



The thirteenth or fourteenth centuries form the closing pe- 

 riod to which we must limit the data of vitrified sites. The 

 English, in their expedition against Scotland, endeavoured to 

 clear the soil from its encumbering woods ; and it is recorded 

 that, in an expedition of the Duke of Lancaster, eighty thou- 

 sand hatchets were heard resounding through the forests, which 

 at the same moment were consumed by spreading fires. Last- 

 ly, as Mr Tytler has added, many districts were soon afterwards 

 brought into cultivation, and converted into fields and meadow, 

 lands. 



After the period of the destruction of Scottish forests, it 

 would be futile to expect that any records would indicate the 

 continuance of vitrifying causes. The hill which, as a signal 

 of war, once proudly blazed with the lavish conflagration of 

 stately trees, is now illumined with little more than a paltry 

 tar-barrel ! Sic transit gloria mundi. 



Recapitulation. — But these investigations I shall now close 

 by stating the conclusions to which I have thus far arrived. 

 They are as follows : — 



1st, That the notion that vitrification is the effect of volcanic 

 agency, as well as the hypothesis which would consider vitri- 

 fication as the result of a regular fabrication for the purpose 

 of cementing stone walls, are conjectures equally chimerical- 



%xlly, That the theory of Lord Woodhouselee, that the con- 

 flagration of wooden ramparts by an assailing enemy might 

 have produced the vitrification in question, is not established 

 in any single instance ; notwithstanding the probability that 

 such a cause might have occasionally subsisted. 



'idly, That the number of vitrified sites in Scotland is re- 

 ferable to the fuel extravagantly consumed during its ancient 

 densely wooded state. 



in the first number of which is an essay by the first-named gentleman upon 

 the vitrified forts of Scotland. The scientific professor has reposed upon 

 the theory of Williams, as revived by I)r Macculloch, which is, I believe, 

 the only one known to continental geologists. There are several valuable 

 observations of ihe writer on the effects of the artificial heat thus induced, 

 when compared with the result of volcanic energy upon rocks of similar 

 character. The resemblance, to which I have myself many years since 

 adverted in various papers which I have read on vitrified forts, is often very 

 striking. 



