75 
animals which formerly roamed over Norfolk and Suffolk, is too 
■well known to need any comment. The in-coming of the Glacial 
cold, — and you will observe that this so-called Torest-bed is older 
than the glacial deposits which here rest upon it, — doubtless either 
exterminated these great pachyderms and carnivores or drove them 
southwards towards those regions which are now tenanted by 
similar forms. What adecpiate record, however, does geology 
supply us with of tliese changes, and how infinitesimal is the 
proportion between the few bones and teeth here preserved, and 
those of the animals of the innumerable generations which have 
intervened between the pre-glacial Elephants and those of our own 
days. Erom whatever pchnt of view we regard the records of 
geology, the fact of their extreme imperfection is forced upon us. 
Jhe strata avc have considered up to this point are, how'cver, 
geologically considered, but as of yesterday. 'J'ho Forest-bed is 
of somewhat similar ago to the Norwich Crag, and of every 100 
shells Avhich tins last deposit contains, something like 95 are 
absolutely identical with those now existing. Lut, now observe, 
another hiatus of enormous extent — these Pliocene beds arc placed 
hero within a few feet of the Eocene deposits, the recent shells of 
which are, in proportion to the extinct species, 5 instead of 
95 per cent. Ihere are no deposits in East Anglia which bridge 
over the interval between the Pliocene Crag and Forest beds, and 
tho.se of Eocene date. Before, however, we pass over this great gulf, 
before wo plunge into the darkness beyond, let us take one 
look behind us, and sec as well as we can how far wo have 
wandered from our own times. I will refer you to one fact only. 
Sir Charles Lyell tells us that the cone of Etna, 11,000 feet in 
height and 90 miles in circumference at its base, has been slowly 
built up since the Pliocene period. In the island of Sicily, 
strata of 1 lioccne a^e, originally deposited at the bottom of 
the IModiterrancan, liave been consolidated into hard limestone 
rock and raised to 3000 feet above the sea level. The historical 
period seems hardly to form an appreciable unit in the com- 
putation, for there arc ancient Greek temples which are built 
of this limestone, and which stand on hills composed of the 
same rock. 
The Tx)ndon Clay is a thick marine deposit, accumulated in 
proximity to land, of sediment brought down by a river flowing 
