a point where the fire lit up the corridor sufficiently for me to see that no soldier of Helium lay between me and the conflagration—what was in it or upon the far side I could not know, nor could any man have passed through that seething hell of chemicals and lived to learn.
Having satisfied my sense of duty, I turned and ran rapidly back to the corridor through which my men had passed. To my horror, however, I found that my retreat in this direction had been blocked—across the mouth of the corridor stood a massive steel grating that had evidently been lowered from its resting place above for the purpose of effectually cutting off my escape.
That our principal movements were known to the First Born I could not have doubted, in view of the attack of the fleet upon us the day before, nor could the stopping of the pumps of Omean at the psychological moment have been due to chance, nor the starting of a chemical combustion within the one corridor through which we were advancing upon the Temple of Issus been due to aught than well-calculated design.
And now the dropping of the steel gate to pen me effectually between fire and flood seemed to indicate that invisible eyes were upon us at every moment. What chance had I, then, to rescue Dejah Thoris were I to be compelled to fight foes who never showed themselves. A thousand times I be-
