velopment. As a social being, he had developed all
the elements of a primitive civilization. If, for convenience of
classification, we speak of his state as savage, or barbaric, we use
terms which, after all, are relative, and which do not shut off our
primitive ancestors from a tolerably close association with our own
ideals. We know that, even in the Stone Age, man had learned how to
domesticate animals and make them useful to him, and that he had also
learned to cultivate the soil. Later on, doubtless by slow and painful
stages, he attained those wonderful elements of knowledge that enabled
him to smelt metals and to produce implements of bronze, and then of
iron. Even in the Stone Age he was a mechanic of marvellous skill, as
any one of to-day may satisfy himself by attempting to duplicate such an
implement as a chipped arrow-head. And a barbarian who could fashion
an axe or a knife of bronze had certainly gone far in his knowledge of
scientific principles and their practical application. The practical
application was, doubtless, the only thought that our primitive ancestor
had in mind; quite probably the question as to principles that might
be involved troubled him not at all. Yet, in spite of himself, he
knew certain rudimentary principles of science, even though he did not
formulate them.

Let us inquire what some of these principles are. Such an inquiry will,
as it were, clear the ground for our structure of science. It will
show the plane of knowledge on which historical investigation begins.
Incidentally, perhaps, it will reveal to us unsuspected affinities
between ourselves and our remote ancestor. Without attempting anything
like a full analysis, we may note in passing, not merely what primitive
man knew, but what he did not know; that at least a vague notion may be
gained of the field for scientific research that lay open for historic
man to cultivate.

It must be understood that the knowledge of primitive man, as we are
about to outline it, is inferential. We cannot trace the development
of these principles, much less can we say who discovered them. Some of
them, as already suggested, are man's heritage from non-human ancestors.
Others can only have been grasped by him after he had reached a
relatively high stage of human development. But all the principles here
listed must surely have been parts of our primitive ancestor's knowledge
before those earliest days of Egyptian and Babylonian civilization,
t