analogous manner.

That vibrations are excited by sound is beautifully exemplified by the
eidophone, an instrument invented, I believe, by Mrs. Watts-Hughes, and
with which I have seen that lady experiment. Dry sand is scattered on a
diaphragm on which the eidophone concentrates the vibrations from music
played near it. The sand, as it were, dances in time to the music, and
when the music stops is found to settle into definite forms, sometimes
like a tree or a flower, or else some geometrical figure, but never a
confused jumble. Perhaps in this we may find the origin of the legends
regarding the creative power of Orpheus' lyre, and also the sacred
dances of the ancients--who knows!

Perhaps some critical reader may object that sound travels by means of
atmospheric and not etheric waves; but is he prepared to say that it
cannot produce etheric waves also. The very recent discovery of
transatlantic telephoning tends to show that etheric waves can be
generated by sound, for on the 20th of October, 1915, words spoken in
New York were immediately heard in Paris, and could therefore only have
been transmitted through the ether, for sound travels through the
atmosphere only at the rate of about 750 miles an hour, while the speed
of impulses through ether can only be compared to that of light or
186,000 miles in a second. It is therefore a fair inference that etheric
vibrations can be inaugurated by sound.

Perhaps the reader may feel inclined to say with the Irishman that all
this is "as dry as ditch-water," but he will see before long that it has
a good deal to do with ourselves. For the present what I want him to
realize by a few examples is the mathematical accuracy of Law. The value
of these examples lies in their illustration of the fact that the Law