atom has been exhausted? At any moment some fortunate incident may reveal a
fresh power. One by one the powers of light have been unfolded.

After thousands of years the telescope opened the stars, the
prism analysed the substance of the sun, the microscope showed
the minute structure of the rocks and the tissues of living
bodies. The winged men on the Assyrian bas-reliefs, the gods of
the Nile, the chariot-borne immortals of Olympus, not the
greatest of imagined beings ever possessed in fancied attributes
one-tenth the power of light. As the swallows twitter, the dim
white finger appears at my window full of wonders, such as all
the wise men in twelve thousand precedent years never even hoped
to conceive. But this is not all--light is not all; light conceals more than
it reveals; light is the darkest shadow of the sky; besides light there are
many other mediums yet to be explored. For thousands of years the sunbeams
poured on the earth, full as now of messages, and light is not a hidden
thing to be searched out with difficulty. Full in the faces of men the rays
came with their intelligence from the sun when the papyri were painted
beside the ancient Nile, but they were not understood.

This hour, rays or undulations of more subtle mediums are
doubtless pouring on us over the wide earth, unrecognised, and
full of messages and intelligence from the unseen. Of these we
are this day as ignorant as those who painted the papyri were of
light. There is an infinity of knowledge yet to be known, and
beyond that an infinity of thought. No mental instrument even has yet been
invented by which researches can be carried direct to the object. Whatever
has been found has been discovered by fortunate accident; in looking for one
thing another has been chanced on. A reasoning process has yet to be
invented by which to go straight to the desired end. For now the slightest