the spinal cord.  Immediately I control every muscle of the rykor’s body—­it becomes my own, just as you direct the movement of the muscles of your body.  I feel what the rykor would feel if he had a head and brain.  If he is hurt, I would suffer if I remained connected with him; but the instant one of them is injured or becomes sick we desert it for another.  As we would suffer the pains of their physical injuries, similarly do we enjoy the physical pleasures of the rykors.  When your body becomes fatigued you are comparatively useless; it is sick, you are sick; if it is killed, you die.  You are the slave of a mass of stupid flesh and bone and blood.  There is nothing more wonderful about your carcass than there is about the carcass of a banth.  It is only your brain that makes you superior to the banth, but your brain is bound by the limitations of your body.  Not so, ours.  With us brain is everything.  Ninety per centum of our volume is brain.  We have only the simplest of vital organs and they are very small for they do not have to assist in the support of a complicated system of nerves, muscles, flesh and bone.  We have no lungs, for we do not require air.  Far below the levels to which we can take the rykors is a vast network of burrows where the real life of the kaldane is lived.  There the air-breathing rykor would perish as you would perish.  There we have stored vast quantities of food in hermetically sealed chambers.  It will last forever.  Far beneath the surface is water that will flow for countless ages after the surface water is exhausted.  We are preparing for the time we know must come—­the time when the last vestige of the Barsoomian atmosphere is spent—­when the waters and the food are gone.  For this purpose were we created, that there might not perish from the planet Nature’s divinest creation—­the perfect brain.”

“But what purpose can you serve when that time comes?” asked the girl.

“You do not understand,” he said.  “It is too big for you to grasp, but I will try to explain it.  Barsoom, the moons, the sun, the stars, were created for a single purpose.  From the beginning of time Nature has labored arduously toward the consummation of this purpose.  At the very beginning things existed with life, but with no brain.  Gradually rudimentary nervous systems and minute brains evolved.  Evolution proceeded.  The brains became larger and more powerful.  In us you see the highest development; but there are those of us who believe that there is yet another step—­that some time in the far future our race shall develop into the super-thing—­just brain.  The incubus of legs and chelae and vital organs will be removed.  The future kaldane will be nothing but a great brain.  Deaf, dumb, and blind it will lie sealed in its buried vault far beneath the surface of Barsoom—­just a great, wonderful, beautiful brain with nothing to distract it from eternal thought.”

“You mean it will just lie there and think?” cried Tara of Helium.