So far as mere material progress is concerned, it may be doubtful
whether anything so epoch-making as the steam-engine or the
telegraph is held in store for us by the future. But in the field
of purely scientific discovery we are finding a crowd of things of
which our philosophy did not dream even ten years ago.

The greatest riddles which the nineteenth century has bequeathed
to us relate to subjects so widely separated as the structure of
the universe and the structure of atoms of matter. We see more and
more of these structures, and we see more and more of unity
everywhere, and yet new facts difficult of explanation are being
added more rapidly than old facts are being explained.

We all know that the nineteenth century was marked by a separation
of the sciences into a vast number of specialties, to the
subdivisions of which one could see no end. But the great work of
the twentieth century will be to combine many of these
specialties. The physical philosopher of the present time is
directing his thought to the demonstration of the unity of
creation. Astronomical and physical researches are now being
united in a way which is bringing the infinitely great and the
infinitely small into one field of knowledge. Ten years ago the
atoms of matter, of which it takes millions of millions to make a
drop of water, were the minutest objects with which science could
imagine itself to be concerned, Now a body of experimentalists,
prominent among whom stand Professors J. J. Thompson, Becquerel,
and Roentgen, have demonstrated the existence of objects so minute
that they find their way among and between the atoms of matter as
rain-drops do among the buildings of a city. More wonderful yet,
it seems likely, although it has not been demonstrated, that these