Bertram Coghill Alan Windle.

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came once more capable of supporting life ; these milder
epochs being again succeeded by glacial conditions. Indeed,
there is nothing to prove that we may not now be in
enjoyment of an inter-glacial epoch of mild character, nor
anything to show that the glaciers may not once more
invade those parts of the world where they are now and have
for ages been unknown, and by their invasion eradicate in
the areas invaded all traces of the civilisation of which we
are now so proud. There is nothing to prove this to be a
dream ; and this because so far we are wholly in the dark as
to the cause of that Ice Age which we know to have existed.
It is hardly necessary to say that a number of theories have
been put forward to account for the extraordinary differ-
ence of the temperature which must have existed at that time
when compared with that which obtains at the present day.
It has been suggested that it may have been due to a varia-
tion in the internal heat of the earth, but that does not
explain the intervals, still less does it explain why we are
not under glacial conditions at this moment. It has been
supposed that the sun may be a variable star and have
periods of darkness during which glacial conditions would
obtain ; or again that it has yellow or warm periods, and red
or cold. There is no real proof that these theories have any
kind of foundation. The idea that the Glacial Period was
due to the passage of the earth through colder regions of
space seems to be untenable. Changes in the distribution
of land and water have been invoked as an explanation
since the days of Lyell, but the most recent researches seem
to throw very grave doubt on this explanation. The theory
that the changes in climate are due to variations in the
amount of carbon dioxide in the atmosphere has also been
put forward, but has failed to meet with any general accept-
ance. There is also a group of explanations based on the
effects of the variation of the elements of the earth's rota-
tion and orbit, such as variations in the obliquity of the
ecliptic, which, it now appears from careful calculations,
could not produce any marked climatic changes.

Possibly a more likely explanation is that of Hann, who
holds that " the simplest and most obvious explanation of


great secular changes in climate, and of the former preval-
ence of higher temperatures in the northern circumpolar
region, would be found in the assumption that the earth's
axis of rotation has not always had the same position, but
that it may have changed its position as the result of
geological processes, such as extended rearrangements of
land and water." This view, which recent observations
seem to have shown to be more tenable than was thought
to be the case when it was first formulated, is still under
discussion, but cannot be said to have secured anything like
general acceptance. Croll's Astronomical Theory has per-
haps secured greater acceptance than any other explanation
so far brought forward. It has its difficulties, but they are
perhaps less than those with which other explanations are
confronted ; but it would be too much to say that this
theory is in any way to be regarded as established. It is
briefly as follows : —

All the planets, the earth included, revolve around the
sun, not in a circle but in an ellipse, and the sun occupies
one of the foci, not the centre of this ellipse. At one end
of its orbit (in perihelion) the earth is much nearer the sun
than it is in the other (in aphelion). Further, the earth's
axis is tilted so that in its journey around its orbit it presents
first one then the other of its hemispheres more directly
to the sun's rays, and at this time it is the southern hemi-
sphere which is presented during perihelion and the northern
in aphelion, but this was not and will not always be the
case. Now, without going further into this matter 1 it may
briefly be said that Croll's Theory refers the glaciation of
Northern Europe and America to a time or times when,
the eccentricity of the earth's orbit being considerably
greater than at the present day, the northern summer
occurred in perihelion.

It is not exactly waste of time to have briefly considered
all these explanations, since they form a good example of
the careful manner in which problems of this kind are con-
sidered by men of science, and further and even more fully
demonstrate the extreme difficulty of assigning a reason

1 This is fully discussed in Chapter XIV of W. B. Wright's ** Quater-
nary Ice Age."


for many events of the occurrence of which we can
entertain no reasonable doubt ; and that even though we
are in possession of so many of the terrestrial, astronomical,
and mathematical data on which the explanation so long
sought and so elusive must necessarily rest.

Any text-book on geology will explain the indications
on which are based our knowledge of the districts which
have existed under glacial conditions during the period in
question, and how we are able to indicate the direction and
ascertain the thickness of the sheets of ice. In the words
of Sollas, if we follow the southern boundary of the ice, we
shall find that it will take us out of Britain and lead us right
across the continent of Europe. After stretching from
Kerry to Wexford, and through the Bristol Channel to
London, it crosses the sea, continues its course through
Antwerp, past Magdeburg, Cracow, Kiev, runs south of
Moscow to Kazan, and then terminates at the southern end
of the Ural mountains. All that lies to the north of this
line — the greater part of the British Isles, Northern Germany,
Scandinavia, and almost the whole of European Russia —
was buried out of sight beneath a mantle of ice formed by
the confluence of many colossal glaciers. At the same time
a large part of North America was overwhelmed. The great
terminal moraine which marks the southern boundary of
the ice can be traced with occasional interruptions from
Nantucket, through Long Island past New York, towards
the western extremity of Lake Erie, then along a sinuous
course in the same direction as the Mississippi ; then it
follows the Missouri as far as Kansas City, and beyond runs
approximately parallel to that river, but south of it, through
Nebraska, Dakota, Montana, and Washington, where it
meets the coast north of Columbia river. Within this
boundary nearly the half of North America was buried be-
neath a thick sheet of ice, flowing more or less radiately out-
wards from a central region situated in and about the
region of Hudson Bay. The coexistence of two continental
ice-caps, continues the same writer, one on each side of the
Atlantic Ocean, is a sufficiently impressive fact, and that
the Ocean itself enjoyed no immunity from the rigours of
the time is shown by the discovery of boulders, which appear


to have been carried by ice, in close proximity to the Azores
(about lat. 38° N.). A review of the evidence may fairly
lead us to conclude that a general lowering of the tempera-
ture, probably to the extent of about 5 C, affected the
whole of the Northern Hemisphere which lies outside the
Tropic of Cancer. We need not delay over the case of the
Southern Hemisphere further than to state that it also
presents its traces of a Glacial Period. In the regions which
we have more particularly been considering, the ice sheets
were of enormous extent, covering something like two million
square miles in Europe and about double that in North
America. They were also of enormous thickness, as the
average depth of the European sheet has been calculated at
one mile and that of the North American at from one to
three miles. G. F. Wright remarks that the ice was cer-
tainly more than one mile deep over New England, for marks
of the movement are found on the summit of Mount Wash-
ington, which is more than six thousand feet high. It is
quite obvious that during this period when such tracts of
ground were covered by such enormous masses of ice no
kind of life could have existed. But it must be remembered
that the ice was not omnipresent, for there were areas of
Europe and of America which were not invaded. G. F.
Wright, who is one of the champions of a recent date for
the Ice Age, even goes so far as to say that " large areas in
Europe and North America which are now principal centres
of civilisation were buried under glacial ice thousands of
feet thick, while the civilisation of Babylonia was at its
heyday." It may at once be admitted that this view,
which will be further considered shortly, is one which would
not be accepted by at least a very large number of glacialists,
but it will serve to impress on one's mind the undoubted
fact that at certain periods of the Ice Age mankind must
have been in existence on some part of the earth whilst
other parts were covered with the immense crusts of ice
with which we have been dealing. But further, there seems
no doubt that the Ice Age was not an era of unbroken and
unvarying cold. On the contrary, there were intervals — how
many is still in dispute — during which warmer climatic con-
ditions prevailed, the ice receded and human existence


became possible in regions where before — and afterwards —
it was quite inconceivable. Here again it must be ad-
mitted that there is not a unanimous opinion in favour of
the existence of genial intervals — still less is there a general
consent, even on the part of those who believe in them, as
to the exact number and relations of these intervals — but the
most generally received view will now be indicated, together
with the chief divergences therefrom. To this it will be
convenient to add the relationship of man, according to
various authorities, to the different subdivisions of glacial
time. In a former chapter we dealt briefly with the geo-
logical history of the earth down to and including the
Pliocene era which we saw was, on the whole, a time of
considerable warmth, the temperature gradually becoming
cooler towards its later part. On this followed the Pleis-
tocene era, which is conterminous with the glacial epoch. 1

There are, as has already been said, differences of opinion
on the question, but the generally received idea is that
there were during the Glacial Period four periods of intense
glaciation, with three milder intervals. Each such milder
interval would, of course, be preluded and led up to by a
time when the glaciers of the preceding period of glaciation
were receding, and in like manner would be terminated by
a period during which the glaciers were gradually resuming
their sway. The last period of glaciation was succeeded by
the recent period — perhaps itself only a genial interval to
be followed by further glaciation — in which we are now

Various names have been given to these periods ; perhaps
the best known classification is that of Penck and
Buckner, which is founded on alpine studies and is named
accordingly, Die Alpen im Eiszeitalter. 2

1 In the following account use has been made of the works below
indicated and the initials added in brackets after each will be employed
for the purpose of avoiding unnecessary repetition. These works may be
consulted by persons desirous of obtaining fuller information on the
subject. Hoernes (H.), " Der Diluviale Mensch in Europa," 1913 ; Sollas
"Ancient Hunters," Macmillan, 191 1 ; Wright, G. F. (G. F.W.), ut
supra; Geikie, Jas. (G.), " The Antiquity of Man in Europe," Oliver &
Boyd, 1914 ; Wright, W. B. (W. B. W.), " The Quaternary Ice Age,"
Macmillan, 1914. This chapter has appeared in a modified form in my
" Century of Scientific Thought."

* P. and B. in the table.


First Glacial Period. Scanian (G.), Gtinz (P. & B.).

This was a period of intense cold. In Britain no records
exist, since they have either been destroyed or buried under
later glacial formations.

First Inter-Glacial Period. Norfolkian (G.), Giinz-
Mindel (P. & B.)

At this time Britain was joined to the Continent of Europe
by land-bridges ; the continuity between the two now
separate portions of land may perhaps best be illustrated
by saying that the Thames was a tributary of the Rhine.
The animals of this period were very different from those
now or in recent times in existence in Europe ; x for amongst
the fauna were the hippopotamus, two kinds of elephant
(E. meridionalis and E. antiquus), the bear, the bison, and
the sabre-toothed tiger. It is possible that the sand-beds
of Mauer in which what is commonly known as the Heidel-
berg mandible was found may belong to this period, for
Geikie states that " the geological and palaeontological
evidence, although not quite decisive, seems to favour the
reference of this ancient human type to the first Inter-
glacial or Norfolkian stage."

Second Glacial Period. Saxonian (G.), Mindel
(P. & B.).

As the ice receded at the termination of the second
glacial period, Europe became subject to what are called
" tundra " conditions — the word tundra, which is Russian
in its origin, is applied to the flat plains which border the
Arctic regions alike in Europe, Asia, and North America.
Treeless and in many places marshy, they endure long periods
of frost during each year, followed by others of cold winds,
with relaxations during which scanty and stunted vegeta-
tion makes its appearance. When, therefore, one speaks of
" tundra " conditions in Central Europe, one refers to a
climate and other conditions similar to that experienced
to-day in a large part of Siberia. It is obvious that

1 It will be obvious that the account given in this table is based on
European data. This is because the questions of chief interest in this
connection, 'which relate to man and his appearance on this earth, are at
the present time mainly associated with European discoveries.


conditions of this kind must exercise a great influence on
the animals and plants at that time striving to exist in the
area in question : indeed it is largely by considering the
character of the fauna and flora that we are able to come to
a conclusion as to the nature of the climate with which
they must have been associated. Prominent amongst the
fauna were the woolly rhinoceros,the musk-ox, the mammoth
and the reindeer. Two of these creatures are of such im-
portance that a few words must be said about them. The
Mammoth (Elepkas antiquus) was a huge elephant, differing
from the elephants now in existence in various ways, but
notably in size ; in being clad with hair, some of it no less
than six feet in length, which enabled it to withstand the
rigours of a climate unsuitable to the elephants of to-day ;
and in the enormous upturned tusks which it possessed.
This creature is not merely known to us by its skeleton, as
is the case with so many extinct animals. It comes under
our notice in two other ways. First of all, as stated in a
previous chapter, it was the object or one of the objects of
the art of early man, where we have vivid and unmistakable
representations of this creature by his human contemporary.
But beyond this, it has been possible for man of the present
day to see this huge beast as he was in the days when he
wandered over Europe, for in the course of those wanderings
in what is now Siberia it was not infrequently his misfortune
to become bogged in a temporarily-thawed ice and mud
bed. Unable to extract himself from the trap into which
he had walked, he perished in it and was subsequently
frozen up and retained in that frozen condition — exactly
like meat in cold storage — until long ages afterwards an
unusually warm season thawed him out in such perfect
condition that it has been possible to discover, by dissection,
the remains of his last meal (pine tops) in an almost
unaltered condition in his stomach. The reindeer, the other
animal of interest, requires no special description, since
being still in existence in northern latitudes it is familiar
to everybody from pictures. It will suffice to point out
that during the time with which we are now concerned and
for many years afterwards this creature was to be found
all over the Continent of Europe.


Second Inter-Glacial Period. Tvrolian (G.) Mindel
Riss (P.).

When the Tyrolian period had been fully established the
climate of Europe was milder even than it is at present ; and
as a consequence, the snow-fields and glaciers of the Alps were
much less extensive than they now are, a fact which throws
a remarkable light on the conditions which then prevailed.
The physical geography of Europe was very different from
that of the present day, for land-bridges connected that
continent with Africa and with the British Isles of to-day.
At that time, it must be remembered, what are now Britain
and Ireland were continuous land — indeed what may be
thought of as the Continent of Europe extended some con-
siderable distance west of what is now the further shore of
Ireland .

The fauna differed remarkably from that of recent times
for "the hippopotamus, elephants, rhinoceroses, cervine
and bovine animals and many carnivores ranged over the
major portion of Europe " (Geikie).

An excellent example of the difference in this respect
may be found in a consideration of the facts learnt from
the study of the Victoria Cave near Settle in Yorkshire — a
place which has afforded shelter to man and beast for many,
many centuries down at least to the time of the Saxon
invasion, when the unhappy Celt, flying from the face of
his foe, made it his place of refuge. It is but a few
miles from Harrogate, where these lines are being written,
and it is safe to say that no larger wild mammal
than a fox would now be discoverable in its vicinity. At
the time with which we are now concerned there were,
as the remains show, the hippopotamus, the rhinoceros
(though not the woolly variety), the straight -tusked elephant,
the bison, the red-deer, the hyaena, and other animals which
need not be mentioned ; and with them and, as far as he
could, no doubt on them, lived man, who was, we may feel
sure, but too often their victim as well as their hunter.

Which of the races of man with whom we have been
concerned in former chapters may we look upon as having
existed at this period ? This is a very pertinent question,


for we have now undoubtedly arrived at a time when we
can consider prehistoric man as a race and not merely as a
thing of fragments like the Heidelberg and perhaps the
Piltdown or the Trinil remains.

There is a considerable difference of opinion on this
matter, for Hoernes, who had already disposed of the
Chelleans and even of the Mousterians by placing them in
the previous genial interval, brings the Solutreans into this
one. It may fairly be said that Geikie's view is one
which commends itself more to the scientific opinion
of the day, in spite of the deservedly high authority of

According to Geikie the Chellean civilisation was associ-
ated with this epoch. Their " rudely fashioned stone im-
plements seldom occur in caves, but are often met with in
the older Pleistocene river-drifts. From this it has been
inferred that Chellean man probably lived in the open, for
the climate was clement and equable, the seasons not being
so strongly contrasted as in our days. The margins of the
rivers were apparently favourite haunts of the race, the
coarse gravels affording an inexhaustible supply of the
stones required for implements."

At its zenith this seems to have been the warmest of the
intervals and it was almost certainly also the longest.
As the climate gradually grew colder, preluding the next
glacial epoch, the hippopotamus, the straight-tusked and
the southern elephants, migrated southwards. The last-
named animal never returned. It was during this period
of transition from genial interval to glacial conditions that,
according to Geikie, the Acheulian civilisation flourished.

Third Glacial Period. Polonian (G.), Riss (P. & B.).

In the period of transition just alluded to and in the
epoch now under consideration, up to what may be called
its climax, Geikie thinks that " man of the Mousterian stage
of culture had come to occupy the caves of north-west,
central, and southern Europe. In England, Belgium,
France, and Germany he was eventually contemporaneous
not only with the mammoth and the woolly rhinoceros, but
with the reindeer, glutton, arctic fox, and other members


of the tundra fauna." This period was not one of such
intense cold as the Saxonian, in which, as already stated,
the glaciers in England extended as far as the valley of the
Thames ; in the epoch under consideration they came no
further south than the Midlands.

Third Inter-Glacial Period. Dumtenian (G.), Riss-
Wurm (P. & B.).

During this genial interval the Alpine glaciers dwindled
very much, as is shown by the following amongst many
other facts. On the Ebenalp and at an elevation of 4800
feet is the cave of Wildkirchli, in which have been found
implements belonging to the Mousterian zone of culture and
with them evidences of a fauna amongst which are the cave-
bear, the cave-lion, the wolf, the stag, and the ibex. Now
it is to be noted that all these animals have also been identi-
fied in the Mentone caves where they are equally associated
with Mousterian implements, as well as with the bones of
the straight -tusked elephant, the broad-nosed rhinoceros,
and the hippopotamus. This shows how mild the climate
must have been even at the elevation of the Wildkirchli
cave. With this period, as well as with that which immedi-
ately preceded it, Geikie associates Mousterian man, that
rugged and hardy individual exampled by the man of the
Neanderthal remains.

On the other hand, Hoernes places Magdalenian man in
this period. We may pause for a moment to consider how
very tentative are all the views which are put forward
respecting this glacial period. According to the classifica-
tion now commonly adopted Mousterian man belongs to
the Middle, Magdalenian to the Younger Palaeolithic epochs.
At any rate there is little doubt that there is a considerable
interval of time between them — some, as we shall see, would
say tens of thousands of years ; yet it will be observed that
two authorities, both of great eminence, put them into the
same era, a thing which both would admit is impossible.
There is, as is only natural in a subject in connection with
which new discoveries are being made every day, a constant
shifting of position on all sorts of questions connected with
the Prehistoric period ; and the uncertainty of many — one


might almost say most — of the views put forward in con-
nection with it is well exemplified by the conflict of opinions
to which attention has just been called. To finish with this
point, Hoernes not only introduces the Magdalenians into
this period, but he goes further for he subdivides it into
two parts. The first of these, characterised by the reindeer,
is Magdalenian ; to the second, characterised by the red-
deer, he assigns the Tourassian and even the Asylian — that
is to say, the transition civilisation, which chronologists
who follow Penck would place at something like one hundred
thousand years' distance from the Mousterians, and who, on
the most modest and moderate estimates, were removed
from them by many long centuries. There is a skeleton
discovered in the Thames Valley, commonly known as the
Galley Hill skeleton, concerning which there has been much
discussion. Keith 1 assigns this skeleton to the period with
which we are now concerned and remarks concerning it :
" The first impression on examining the remains of this
earliest known inhabitant of England is one of surprise,
almost of disappointment ; in all his features, with a few
exceptions, he is so modern in build that we might meet
him on the streets of London to-day and pass him by un-
noted." 2

Fourth Glacial Period. Mecklenburgian (G.), Wiirm
(P. &B.).

This seems to have been a less severe period of cold than
the preceding glacial periods. According to Geikie " the
younger archaeological stages — the Aurignacian, the Solu-
trean, and the Magdalenian — are closely related to this
epoch, the mammalian fauna indicating, for the first -named
stages, a somewhat cold climate (as in the cave at Mentone

1 " Ancient Types of Man," Harpers, 191 1, p. 32.

2 A few lines above it was remarked that the fluctuating character of

Online LibraryBertram Coghill Alan WindleThe church and science → online text (page 23 of 38)