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
heat ether.

"Their discoveries show that the atmospheric etheric envelope of
each etheric atom is made up of etheric atoms of different
vibratory powers. As the atmosphere of the earth is made up of
atoms of oxygen and nitrogen and argon, so that of an atom is
made up of three kinds of ethers, corresponding to three of our
senses. That it consists of five ethers, corresponding to our
five senses, as the ancient Hindus assert--who can say?

"I mention this subject of the differentiation of the ether
merely that you may not suppose that the ether is a simple
substance. For the present we will treat it as a simple
substance, but next year we will take it up as a compound one.

"This steel bar before you is not one bar, but two bars. There
is a visible bar and an invisible bar, the visible bar being made
of physical atoms, and the invisible bar of etheric atoms. The
etheric bar is invisible, but it is made of matter, the same as
the visible bar, and it is just as real, just as truly a bar as
the one we see.

"More than this. The etheric, invisible bar is the source and
cause of all phenomena connected with the bar. It is the real
bar, and the one we see is merely the shadow in physical matter
of a real bar. In shape, strength, color, in short, in
everything, it depends on the inv