19 
islands, Ireland probably an archipelago; ‘‘ the British Islands,’’ 
says Jukes Brown, ‘had never been so deeply submerged since 
the commencement of Mesozoic times.” Towards the end of the 
movement, ‘‘it would seem that little of England or Wales could 
have remained above the level of the sea.’’ And in this sea which 
must necessarily have been a deep one, 400 or 500 fathoms—the 
White Chalk was deposited to the thickness of 1,300 feet in the 
east, but much less westward, especially in Antrim because of the 
lateness of the submergence there. At this epoch it is certain 
that the greater part of western and southern Europe was 
covered by an ocean which may have been continuous from the 
southern part of North America, across the Atlantic, and through 
Kurope into Asia.” 
If I have been able at all to impress on your minds a fairly clear 
picture of the great depression of the British Isles at the time 
when the White Chalk was being deposited, it will not be very 
difficult to follow out the successive changes which occurred after- 
wards. They are all due, it must be borne in mind, simply to 
alternate upheavals and subsidences, representing the mighty 
secular pulsations and throbbings of our globe, which seem never 
to have ceased, and which can be detected even at the present time, 
Starting then from the times of this great Cretaceous Sea, when 
only the very highest parts of our islands stood above water, a 
gradual upheaval of the western portion of the European 
continent commenced, until the greater part of the British 
Islands emerged as one continuous area, connected with the 
continent by way of Cornwall, Devon, and Brittany. Probably, 
the rising was more rapid to the west, for Belgium remained 
covered long after the emergence of our cwn country. 
Certainly the first parts to become land would be the mountainous 
and hilly districts of Scotland, Ireland, and Wales ; and along the 
shoreline no doubt fresh deposits were laid down, but if so they 
have been completely removed by denudation ; in England nothing 
comes between the Chalk and the Eocene beds, to be referred to 
presently. The elevation must have amounted to at least 600 feet 
above the present level, and it was probably three or four times as 
much. We must remember that this new land-surface was the 
former bed of the chalk ocean, so that there would be ‘ broad 
- plains of chalk uniting Wales to the Pennine Chain, and Ireland to 
both England and Scotland,” as well as covering all middle, 
eastern, and southern England. And over these of course all the 
atmospheric forces would have free play as at present; the rains 
fell and formed springs, these produced rivers and streams which 
cut and carved the surface into valleys, and, assisted by frost 
carried on the work of denudation. 
