

Of 





a 



m 



Oll« 





tTl 



•^ 



lieUtger 



The heart. 



with 



* 



StUBipj, 



nioi'tiij.^ 



■pendent,' najs 



'inbeDeatli, 

 bug both r»)t 



Ills 



«*■ filling Dp the 



■ . jA to the 

 ' - in diameter. 



pplring 





n. 



...nted in a 

 ]i was fourteen 

 1 roots of fr) 



U 



♦^f 



and pie^'^' 



the c^i'^ 



In 



feet an^ ' 







^s 



PC hOff^^^^, 







^«^ 



n 



'v 



t * 





Ch. xlvi.] 



IN SUBAQUEOUS DEPOSITS. 



531 



tended far lower, and that its extremity consisted, as at 

 present, of rougli and boggy ground, partly clothed with fir- 



I 



trees. It is also probable that the whole of this rested on 

 the sand and pebbles already mentioned, and that the sea, in 

 its progressive encroachments, eventually laid bare, at low 

 Avater, the foundations of this marshy OTOund; in which 



case, much of the sand constituting these foundations might 

 have been washed out by the rapid descent of the fresh water 



them at 

 3 matter 



fall of the tide. The superstratum of 



roots of trees, would not be washed away, but 

 undermined, and thus sink down below the level of t 

 until the waves washed sand and shingle over it. 



might 



This 



may 



have also been assisted by the occasional 

 damming up of the brook by the sand and shingle thrown up 

 during storms. Mr. Harris informs me that such an obstruc- 

 tion actually occurred in the years 1818 and 1824, and the 



bed of the brook was 

 occasions an artificial < 



com 



immediately 



On these 



cut : had 



this, however, not been done, the lower part of the valley 



means the under 



would have become more 



mented 



water to escape through them. In confirmation of this 



hypothesis we may observe, that small streams of freshwater 



often pass under the sands of the sea-beach, so that they 



may be crossed dryshod, whilst the water where it issues 



again, may be seen to carry out sand and pebbles with great 

 rapidity. 



The Eev. W. B. Clarke, after examining the Bournemouth 

 submarine peat and several other similar deposits on the 

 north side of Poole Harbour, came, in 1838, to a conclusion, 



Harris and myself, that they 



submerfjed in modern times 



minm 



imply a general subsidence or change of level in that part of 



the coast.^ 



* On Peat-bogs and Submarine Forests of Bourne Moutli. Eev. W. B, Clarke, 

 Proc. of Gaol. Soe., p. 599. 1838. 



M M 2 



