372 Reviews — G. Re id — Submerged Forests. 



Reference is made to the Pleistocene accumulations of the Dogger 

 Bank and to the recent observations of Messrs. H. Whitehead and 

 H. H. Groodchilii, who obtained from the Bank loose masses of peat, 

 known to the fishermen as 'moorlog'. Samples of this, examined 

 by Mr. and Mrs. Reid, yielded a highly interesting series of plant- 

 remains, and also of insects which were determined by Mr. G. C. 

 Champion, all of species still living in Britain. The occurrence of 

 this peat indicates a sunken land-surface or submerged forest at a 

 depth below sea of about 60 feet or more. It is remarked that "the 

 lowest submerged land-surface is found in Holland at just about the 

 same depth as it occurs in England, and probably on the Dogger 

 Bank also". Further, it is suggested that on this Bank the 

 Pleistocene deposits maj' have " formed islands in the ancient fen, 

 as they do now in East Angiia, Holderness, and Holland ". It should 

 be noted that the Pleistocene fossils of the Dogger Bank have been 

 known for a longer period than "the last .50 years". In the 

 Geological Magazine for 1878 (p. 443) a figure is given of the 

 lower jaw of a mammoth dredged off the Dogger Bank in 1837. 



The evidence of the submerged forests of Lancashire and the Bristol 

 Channel again points to subsidence of about 60 feet, while data 

 obtained in the excavations at the Celtic village of lake-dwellings at 

 Glastonbury ai'e mentioned as indicating that the movement of 

 subsidence ceased "probably not more than 3,500 years ago". 



Interesting particulars and conclusions are given respecting the 

 English Channel and the submerged forests generally, in the south of 

 England from Pegwell Bay to Cornwall. Some account is also given 

 of the severance of Great Britain from the Continent. The areas 

 were connected probably in Newer Pliocene times by a low divide, 

 an extension of the Chalk of the North Downs. " Afterwards, during 

 the Glacial epoch, when an ice-sheet accumulated and blocked the 

 northern outlet of the North Sea, the water was ponded back in the 

 southern part. There was no easy outlet northward for the water of 

 the Rhine and other great rivers, so the level of the North Sea rose 

 slightly till it overflowed this low col and cut an outlet where lies the 

 present Strait of Dover." Subsequent elevation obliterated the 

 Strait, and "converted a great part of the North Sea into a wide 

 alluvial plain". When subsidence initiated the formation of the 

 submerged forests the Strait again became an open channel, which 

 has been gradually widened and deepened. 



The author points out that much subuiarine erosion has taken place: 

 that " tidal scour may go on at any depth, provided the current is 

 confined to a narrow channel", and the Atlantic swell, may remove 

 coarse sand at depths of at least 50 fathoms. In the English Channel 

 the troughs coincide with lines of tidal scour, and do not usually 

 continue the lines of existing valleys, while the continental platform 

 " is in all probability in the main a feature formed by the deposition 

 of sediment during long ages ". 



In East Angiia the Norfolk Broads are regarded as directly 

 associated with the subsidence connected with the submerged forests. 

 In the south of England Romney Marsh and Pevensey Level are 

 considered to be submerged flat-bottomed valleys that have been 



