surrounding it, and these in turn raise the rate of vibration in
the etheric atoms surrounding the physical atoms of your hand.
This rate of vibration in your nerves causes a sensation, or
mental impression, you call "heat." Consciousness of it comes
through your sense of touch; but after all it is merely a "rate
of vibration" which your brain recognizes and names.

"The bar has now reached a temperature of about 700 degrees, and
has become a dull red. Why do you say the color has changed, and
why do you say red?

"Because the rate of vibration of the etheric atoms in the bar is
now about 412 trillions per second, and this rate of vibration
having been imparted to the ether of the air, has in turn been
imparted to the ether of your eye, and this rate of vibration in
the ether of the nerves of your eye your brain recognizes and
calls 'red.'

"The heat still continues and increases. You now have both heat
and light. So you see that the ether is not vibrating in a
single note, but in two chording notes, producing light and heat.
There are two kinds of ether around the iron atom. There is
sound also, but the note is too high for one's ears. It is a
chord of three notes.

"Professor Silliman, of Yale, discovered over twenty years ago,
that the ether could be differentiated into the luminiferous, or
light ether, and the sonoriferous, or sound ether.

"Other great scientists since then have found a third ether--the