The truth of Zarlah’s words flashed upon me, and with it a full realization of the terrible mistake I had made.  In the eyes of Zarlah I was a Martian, her life-long friend, Almos, and her anxiety for me to return to the observatory was the prompting of her Martian sense of duty—­her sole creed.  In what words could I ever hope to explain that I was not Almos, when the voice, the manners, the features, and even the knowledge of her affairs were those of her intimate friend?  And even if it were possible to make Zarlah believe in the remarkable change of personality, by explaining in full the weird and uncanny details of how the change was effected, what happiness could I hope to derive from it; it was Almos she loved, not a strange spirit of whom she could know nothing—­a spirit even from an alien world.

Such were the thoughts that filled my mind, as I walked beside Zarlah through this more than Edenic garden toward the entrance where Reon was to wait for me.  But, although utterly crushed by the realization of my own hopeless case, I felt that the knowledge of Zarlah’s love, of which I had so wrongly come into possession, had imposed upon me a sacred duty.  I therefore gave no outward evidence of my emotions, though my cup of happiness was now changed to one of sorrow and bitterness, and when Zarlah proposed that we should meet the following evening, I quickly assented with all a lover’s eagerness.

We had now reached the entrance and, as we stepped out on the balcony, I saw Reon waiting for me with the aerenoid in readiness.  Seeing a merry party in a large open aerenoid, and knowing them to be Zarlah’s friends, I would have escorted her to them, but in a low tone she earnestly besought me to lose no time in reaching the observatory.

A few words of farewell—­a slight pressure of hands, and we parted; and as I walked over to where Reon stood, ready for the journey, I could not help marveling at the great sacredness in which all duties are held in the eyes of the Martians; duties, too, that have no other reward than their own fulfillment.  A feeling of shame came over me as I thought of the endless struggle, selfishness, and crime of another world that is a slave to Gold.

CHAPTER VIII.

A hundred miles A minute in an aerenoid.

Reon was at his place by the levers when I stepped into the aerenoid, and as I closed and fastened the steel door, we slowly rose, and describing a large circle, sailed toward the canal.  As the sun was now low in the heavens, numerous open aerenoids were to be seen, but these were soon passed, and within a few minutes we had reached the branch canal where our speed increased.