455 
In East Norfolk land has been gained, as at Yarmouth, which, 
to quote Lyell, “first became habitable ground about the year 1008, 
from which time a line of dunes has gradually increased in height 
and breadth, stretching across the whole entrance of the anciLt 
estuary, and obstructing the ingress of the tides so completely that 
they are only admitted by the narrow passage which the river keeps 
open, and which has gradually shifted several miles to the south. ”* 
Thus while the form of the ground is natural, its various irregu- 
larities being duo to excavation, we can assign no particular date^o 
its sculpture, excepting that it was subsequent to the Glacial period; 
for the very agents that have caused it are still at work, though iii ' 
a more or less modified degree. * 
Before vegetation had covered the land, denuding forces could 
have acted with much greater facility, as they can now on 
St. James’ Hill, where human agency assists Nature in the work 
of destruction, and on our cliffs where streams of mud flow out to 
sea across the sands. But so soon as the conditions were favourable, 
and our land still formed part of the Continent, the various plants 
and animals composing our modern fauna and flora, including 
several species that have since become extinct, made their homes in 
the land. 
To plimt-life our scenery is of course most largely indebted, and 
the earlier settlers included the Oak, Ash, Willow, Poplar, Alder 
Birch, Beech, Hornbeam, Pine, Holly, and Yew ;-some specially 
suited to the moist alluvial tracks, others to clayey soil, and a few 
to dry, sandy elevations. Forests of Oak probably occupied the 
greater part of our low-lying clay districts, while the underwood con- 
sisted of Hazel, Blackthorn, Hawthorn, Elder, Brambles, and Briars. 
With the animals, it may be thought, our subject is but little 
concerned; yet Gilpin has remarked that, “no landscape is com- 
plete without its figures.” Hany of the forms that graced the 
scene in the earlier portion of the period we are now considerimr 
have become exterminated; but to most of us the enjoyment of 
scenery is not lessened' by the absence of the Brown Bear and the 
\\ olf. We might indeed welcome an occasional colony of Beavers 
whose habits form so interesting a study, and contribute in no small 
degree to modify their surroundings ; while herds of Boe Deer, 
* ‘ Principles of Geology ’ [li] vol. i. p. 521. 
