Vol. 60.] ANNIVERSARY ADDRESS. d 



of oak and other trees, is found at a depth of 40 to 50 feet below 

 high-water mark, beneath a deposit of marine warp. A higher land- 

 surface is marked by a second sunk forest, seen on the foreshore 

 above the warp, and indicating a submergence of about 4 or 5 feet. 

 At Grimsby, also, a former land-surface, probably continuous with 

 the older one at Hull, has been reached at a depth of 35 feet and 

 more below high-water mark. It may point to a submergence 

 of perhaps as much as 52 feet. 1 In the Fenland district, at least 

 five buried forests have been observed, each characterized by its own 

 vegetation. 2 



On the coast of South Wales, interesting sections have been 

 laid open in the excavation for the Barry Docks, in Glamorgan. 

 These furnish conclusive proof of a succession of at least four layers 

 of peat overlain by estuarine deposits, and in a situation which 

 precludes any recourse to local settlement by drainage of under- 

 ground water or downward slipping. The strata are manifestly 

 undisturbed, and the lowest is an unmistakable land-surface. It 

 consists of peat fall of remains of oak, hazel, cornel, hawthorn, and 

 willow, together with crushed shells of Hyalinia and, apparently, 

 Pisidium and Planorbis. The soil underneath this forest-growth 

 has yielded specimens of Helir, Hyalinia, Succinea, Limncea, Pupa, 

 and Valvata. This buried forest-growth lies at a depth of 35 feet 

 beneath Ordnance-datum, or 55 feet beneath the line of high-water 

 of ordinary spring tides. It proves a submergence of at least 55 

 feet, and the peat-bands at higher levels mark successive pauses in 

 this submergence. That the movement was in progress in Xeolithic 

 time may be concluded from the occurrence of a portion of a polished 

 celt in the uppermost layer of peat, from which also two bone-needles 

 are reported to have been obtained. 3 Mr. Strahan informs me that, 

 wherever excavations have been made at the mouths of the vallevs 

 on the coast of South Wales, similar layers of peat have been cut 

 through at depths below low-water mark. It would thus appear 

 that the submergence has been general all along the coast-line. 



On the Southern English coast similar evidence of a considerable 



1 See S. V. Wood, Jim., & J. L. Rome, Quart. Journ. Geol. Soc. vol. xxiv 

 (1868) p. 157 ; also Clement Reid, ' Geology of Holderness' Mem. Geol. Surv. 

 (1885) p. 77. 



2 S. B. J. Skertchly, ' Geology of the Fenland ' Mem. Geol. Surv. (1877) p. 16i>. 



3 A. Strahan, Quart. Journ. Geol. Soc. vol. lii (1896) p. 474, and the 

 •Geology of Newport' (1899) and 'Geology of Cardiff' (1902) in the Memoirs 

 of the Geological Survey. Further evidence of the submergence of the rock- 

 valleys of South Wales. Devon, and Cornwall, will be found in Mr. Codrington's 

 paper, already cited on p. xcviii. 



