u 
453 
THE WEST OF ENGLAND AND EAST OF WALES. 
X. Tasunar View oF THE Successive Stages oF THE GREAT GLACIAL SUBMERGENCE DURING WHICH THE BOULDERS OF THE 
alan. West or Enetanp anp Norta WALES MAY HAVE BEEN TRANSPORTED. alesis 
2000 2000 
Arenig boulders on Moel Gamelin, up to 1897 feet. 
Continuance of the Arenig dispersion. 
1800 1800 
Arenig boulders on Cyrn-y-Brain and Cefn-y-fedw. 
Continuance of the Arenig dispersion. 
1600 1600 
Continuance of the Arenig dispersion—Boulders around Grouse-box hill, near Llangollen. 
Probable close of the southerly Lake-district felspathic dispersion. : 
1400 1400 
Criffel-granite boulders east of Macclesfield—Hskdale and Criffel-granite pebbles on Moel-y-Tryfaen. 
Continuance of the Arenig dispersion—Arenig boulders around Eryrys, and on the Eglwyseg plateau, near Llangollen. 
1200 Hskdale-granite boulders east of Macclesfield. abe 
Arenig boulders around the Clent and Lickey hills. 
Free exit of Arenig boulders from North-central Wales by way of the Dee valley—Boulders around Chirk, Welsh Frankton, &e. 
1000 1000 
Probable commencement of the Arenig dispersion to distances greater than the immediate vicinity of the mountain. 
800) 53... 5 = 800 
Hskdale-granite boulders around Burton, Shropshire. {north and Bushbury, vid Wolverhampton. 
Criffel-granite boulders south and south-east of the Wrekin and Ashley Heath waterparting, including those between Bridge- 
Boulders intercepted by the Peckforton hills, Ashley Heath, &c. 
600 600 
Probable commencement of the dispersion of the boulders over the Wrekin and Ashley waterparting. 
Close of the Criffel initial dispersion over the south-west part of the Cumberland plain. 
400 400 
Boulders intercepted by the Delamere hills, &c. 
Local and northern boulders in lower gravelly loam and sand of West Shropshire and Denbighshire plain. 
200 200 
The boulders at the base and in the mass of the Cheshire and Lancashire Lower Boulder-clay may have been transported while 
Present |. the sea was shallow, or after its depth exceeded 200 feet, and yet before much of the clay was accumulated. Present 
sea-level. sea-level, 
It is least presumptuous to assume that during the submergence the relative levels of different areas were much the same as at 
present, until the contrary can be proved. 
a 
