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nothing like an inch of chalk has accumulated during the life of a
Crania； and； on any probable estimate of the length of that life；
the chalk period must have had a much longer duration than that
thus roughly assigned to it。
Thus； not only is it certain that the chalk is the mud of an
ancient sea…bottom； but it is no less certain； that the chalk sea
existed during an extremely long period； though we may not be
prepared to give a precise estimate of the length of that period in
years。 The relative duration is clear； though the absolute
duration may not be definable。 The attempt to affix any precise
date to the period at which the chalk sea began； or ended； its
existence； is baffled by difficulties of the same kind。 But the
relative age of the cretaceous epoch may be determined with as
great ease and certainty as the long duration of that epoch。
You will have heard of the interesting discoveries recently made；
in various parts of Western Europe； of flint implements； obviously
worked into shape by human hands； under circumstances which show
conclusively that man is a very ancient denizen of these regions。
It has been proved that the old populations of Europe； whose
existence has been revealed to us in this way； consisted of
savages； such as the Esquimaux are now； that； in the country which
is now France； they hunted the reindeer； and were familiar with the
ways of the mammoth and the bison。 The physical geography of
France was in those days different from what it is nowthe river
Somme；＇69＇ for instance； having cut its bed a hundred feet deeper
between that time and this； and； it is probable； that the climate
was more like that of Canada or Siberia； than that of Western
Europe。
The existence of these people is forgotten even in the traditions
of the oldest historical nations。 The name and fame of them had
utterly vanished until a few years back； and the amount of physical
change which has been effected since their day； renders it more
than probable that； venerable as are some of the historical
nations； the workers of the chipped flints of Hoxne or of Amiens ＇70＇
are to them； as they are to us； in point of antiquity。
But； if we assign to these hoar relics of long…vanished generations
of men the greatest age that can possibly be claimed for them； they
are not older than the drift； or boulder clay； which； in comparison
with the chalk； is but a very juvenile deposit。 You need go no
further than your own sea…board for evidence of this fact。 At one
of the most charming spots on the coast of Norfolk； Cromer； you
will see the boulder clay forming a vast mass； which lies upon the
chalk； and must consequently have come into existence after it。
Huge boulders of chalk are； in fact； included in the clay； and have
evidently been brought to the position they now occupy； by the same
agency as that which has planted blocks of syenite from Norway side
by side with them。
The chalk； then； is certainly older than the boulder clay。 If you
ask how much； I will again take you no further than the same spot
upon your own coasts for evidence。 I have spoken of the boulder
clay and drift as resting upon the chalk。 That is not strictly
true。 Interposed between the chalk and the drift is a
comparatively insignificant layer； containing vegetable matter。
But that layer tells a wonderful history。 It is full of stumps of
trees standing as they grew。 Fir…trees are there with their cones；
and hazel…bushes with their nuts； there stand the stools of oak and
yew trees； beeches and alders。 Hence this stratum is appropriately
called the 〃forest…bed。〃
It is obvious that the chalk must have been up…heaved and converted
into dry land； before the timber trees could grow upon it。 As the
boles of some of these trees are from two to three feet in
diameter； it is no less clear that the dry land this formed
remained in the same condition for long ages。 And not only do the
remains of stately oaks and well…grown firs testify to the duration
of this condition of things； but additional evidence to the same
effect is afforded by the abundant remains of elephants；
rhinoceroses； hippopotomuses and other great wild beasts； which it
has yielded to the zealous search of such men as the Rev。 Mr。 Gunn。＇71＇
When you look at such a collection as he has formed； and bethink
you that these elephantine bones did veritably carry their owners
about； and these great grinders crunch； in the dark woods of which
the forest…bed is now the only trace； it is impossible not to feel
that they are as good evidence of the lapse of time as the annual
rings of the tree…stumps。
Thus there is a writing upon the walls of cliffs at Cromer； and
whoso runs may read it。 It tells us； with an authority which
cannot be impeached； that the ancient sea…bed of the chalk sea was
raised up； and remained dry land； until it was covered with forest；
stocked with the great game whose spoils have rejoiced your
geologists。 How long it remained in that condition cannot be said；
but 〃the whirligig of time ＇72＇ brought its revenges〃 in those days
as in these。 That dry land； with the bones and teeth of generations
of long…lived elephants； hidden away among the gnarled roots and
dry leaves of its ancient trees； sank gradually to the bottom of
the icy sea； which covered it with huge masses of drift and boulder
clay。 Sea…beasts； such as the walrus； now restricted to the
extreme north； paddled about where birds had twittered among the
topmost twigs of the fir…trees。 How long this state of things
endured we know not； but at length it came to an end。 The upheaved
glacial mud hardened into the soil of modern Norfolk。 Forests grew
once more； the wolf and the beaver replaced the reindeer and the
elephant； and at length what we call the history of England dawned。
Thus you have within the limits of your own county； proof that the
chalk can justly claim a very much greater antiquity than even the
oldest physical traces of mankind。 But we may go further and
demonstrate； by evidence of the same authority as that which
testifies to the existence of the father of men； that the chalk is
vastly older than Adam himself。
The Book of Genesis informs us that Adam； immediately upon his
creation； and before the appearance of Eve； was placed in the
Garden of Eden。 The problem of the geographical position of Eden
has greatly vexed the spirits of the learned in such matters； but
there is one point respecting which； so far as I know； no
commentator has ever raised a doubt。 This is； that of the four
rivers which are said to run out of it； Euphrates and Hiddekel ＇73＇
are identical with the rivers now known by the names of Euphrates
and Tigris。
But the whole country in which these mighty rivers take their
origin； and through which they run； is composed of rocks which are
either of the same age as the chalk； or of later date。 So that the
chalk must not only have been formed； but； after its formation； the
time required for the deposit of these later rocks； and for their
upheaval into dry land； must have elapsed； before the smallest
brook which feeds the swift stream of 〃the great river； the river
of Babylon；〃＇74＇ began to flow。
Thus； evidence which cannot be rebutted； and which need not be
strengthened； though if time permitted I might indefinitely
increase its quantity； compels you to believe that the earth； from
the time of the chalk to the present day； has been the theatre of a
series of changes as vast in their amount； as they were slow in
their progress。 The area on which we stand has been first sea and
then land； for at least four alternations； and has remained in each
of these conditions for a period of great length。
Nor have these wonderful metamorphoses of sea into land； and of
land into sea； been confined to one corner of England。 During the
chalk period； or 〃cretaceous epoch；〃 not one of the present great
physical features of the globe was in existence。 Our great
mountain ranges； Pyrenees； Alps； Himalayas； Andes； have all been
upheaved since the chalk was deposited； and the cretaceous sea
flowed over the sites of Sinai and Ararat。
All this is certain； because rocks of cretaceous； or still later；
date have shared in the elevatory movements which gave rise to
these mountain chains； and may be found perched up； in some cases；
many thousand feet high upon their flanks。 And evidence of equal
cogency demonstrates that； though； in Norfolk； the forest…bed rests
directly upon the chalk； yet it does so； not because the period at
which the forest grew immediately followed that at which the chalk
was formed； but because an immense lapse of time； represented
elsewhere by thousands of feet of rock； is not indicated at Cromer。
I must ask you to believe that there is no less conclusive proof
that a still more prolonged succession of similar changes occurred；
before th