if only I knew the force that would change the number or modify the
vibrations of these ions composing the various atoms.

"Now for years I have been seeking that force or combination of forces
that would enable me to produce this change in the elements--raising
or lowering them in the scale, so to speak. I have found it. I am not
going to tell you or any other man whom you may interest the secret of
how it is done until I find some one I can trust as I trust myself.
But I am none the less willing that you should see the results. If
they are not convincing, then nothing can be."

He appeared to be debating whether to explain further, and finally
resumed: "Matter thus being in reality a manifestation of force or
ether in motion, it is necessary to change and control that force and
motion. This assemblage of machines here is for that purpose. Now a
few words as to my theory."

He took a pencil and struck a sharp blow on the table. "There you have
a single blow," he said, "just one isolated noise. Now if I strike
this tuning fork you have a vibrating note. In other words, a
succession of blows or wave vibrations of a certain kind affects
the ear and we call it sound, just as a succession of other wave
vibrations affects the retina and we have sight. If a moving picture
moves slower than a certain number of pictures a minute you see the
separate pictures; faster it is one moving picture.

"Now as we increase the rapidity of wave vibration and decrease the
wave length we pass from, sound waves to heat waves or what are known
as the infra-red waves, those which lie below the red in the spectrum
of light. Next we come to light, which is composed of the seven colors