I explained that I had escaped from the Warhoons and was dying ofstarvation and exhaustion.

"You wear the metal of a green warrior and are followed by a calot,yet you are of the figure of a white man. In color you are neithergreen nor white. In the name of the ninth day, what manner ofcreature are you?"

"I am a friend of the yellow men of Barsoom and I am starving. In thename of humanity open to us," I said in reply.

Presently the door commenced to recede before me until it had sunkinto the wall fifty feet, then it stopped and slid easily to theleft, exposing a short, narrow corridor of concrete, at the furtherend of which was another door, similar in every respect to the one Ihad just passed. No one was in sight, yet immediately we passed thefirst door it slid gently into place behind us and receded rapidlyto its original position in the front wall of the building. As thedoor had slipped aside I had noted its great thickness, fully twentyfeet, and as it reached its place once more after closing behind us,great cylinders of steel had dropped from the ceiling behind it andfitted their lower ends into apertures countersunk in the floor.

A second and third door receded before me and slipped to one side asthe first, before I reached a large inner chamber where I found foodand drink set out upon a great stone table. A voice directed me tosatisfy my hunger and to feed my calot, and while I was thus engagedmy invisible host put me through a severe and searchingcross-examination.

"Your statements are most remarkable," said the voice, on concludingits questioning, "but you are evidently speaking the truth, and itis equally evident that you are not of Barsoom. I can tell that bythe conformation of your brain and the strange location of yourinternal organs and the shape and size of your heart."