The struggle to keep alive during the cold period was terrible. Many
races of men and animals, whose bones we have found, disappeared from
the face of the earth.
Whole tribes and clans were wiped out by hunger and cold and want.
First the children would die and then the parents. The old people were
left to the mercy of the wild animals who hastened to occupy the
undefended cave. Until another change in the climate or the slowly
decreasing moisture of the air made life impossible for these wild
invaders and forced them to find a retreat in the heart of the African
jungle where they have lived ever since.
This part of my history is very difficult because the changes which I
must describe were so very slow and so very gradual.
Nature is never in a hurry. She has all eternity in which to accomplish
her task and she can afford to bring about the necessary changes with
deliberate care.
Prehistoric man lived through at least four definite eras when the ice
descended far down into the valleys and covered the greater part of the
European continent.
The last one of these periods came to an end almost thirty thousand
years ago.
From that moment on man left behind him concrete evidence of his
existence in the form of tools and arms and pictures and in a general
way we can say that history begins when the last cold period had become
a thing of the past.
The endless struggle for life had taught the survivors many things.
Stone and wooden implements had become as common as steel tools are in
our own days.
Gradually the rudely chipped flint axe had been replaced by one of
polished flint which was infinitely more practical. It allowed man to
attack many animals at whose mercy he had been since the beginning
of time.
The mammoth was no longer seen.
The musk-ox had retreated to the polar circle.
The tiger had left Europe for good.
The cave-bear no longer ate little children.
The powerful brain of the weakest and most helpless of all living
creatures--Man--had devised such terrible instruments of destruction
that he was now the master of all the other animals.
The first great victory over Nature had been gained but many others were
to follow.
Equipped with a full set of tools both for hunting and fishing, the
cave-dweller looked for new living quarters.
The shores of rivers and lakes offered the best opportunity for a
regular livelihood.
The old caves were deserted and the human race moved toward the water.
Now that man could handle heavy axes, the felling of trees no longer
offered any great difficulties.
For countless ages birds had been constructing comfortable houses out of
chips of wood and grass amidst the branches of trees.
Man followed their example.