“If you put your hand anywhere near the bar you will feel a sensation called heat, and say it has become hot.  The reason for that is that you are in actual and literal touch with the bar or iron through the ether.  It is not alone each atom of the bar of iron that is surrounded by the ether, but each atom of the air, and each atom of your body.  Their etheric atmospheres are all touching, and the increase in the vibration of the ether surrounding the atoms of iron is imparted to those of the air 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 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.