“I am not in any mood to utter empty threats, but I am speaking no idle words when I tell you that the hour in which you make war on Christendom, either for political or religious conquest, shall be the hour in which you will hear the voice of Destiny speaking your own doom. “More than that, I ask you now to pledge me your word as an honest man and a ruling King that for twelve months from now, at the very least, you will neither draw a sword nor fire a shot either against Anglo-Saxondom or any other Power.” He stopped, and took his hand from the Sultan’s shoulder. Khalid recoiled and drew himself up to the full height of his royal stature as he replied-- “Prince of the Air--demi-god almost as you are--you must learn that the Commander of the Faithful is not to be dictated to on the roof of his own palace, even by you. Am I your slave that you should lay these commands upon me?” Before he made any reply in words Alan communicated a few rapid orders to those in command of the two air-ships in the Aerian sign-language. The _Ithuriel_ rose from above the _Vindaya_, as the Russian air-ship was named, and both vessels ranged themselves alongside the front of the terrace. The Sultan watched this manœuvre in helpless silence, well knowing that whatever it imported he was powerless to resist. Then Alan went on-- “Not my slave, Sultan, but my fellow-man, and as such I will, if I can, and by any means within my power, prevent you from committing such a colossal crime as that which I am afraid I must now believe you are contemplating. Now listen well, for my words mean much. “Those two air-ships could lay your capital, vast and splendid as it is, in ruins before to-morrow’s sun rises, and as surely as those stars are shining above us they shall do so unless you give me the pledge I ask for. I ask it in the name of all humanity, and I will not spare a few thousands of lives to enforce it.” “If you could!” ejaculated the Sultan, half involuntarily. “I have heard much of your wonderful air-ships, but do you know that I have a hundred thousand soldiers in the city, and that I have hundreds of guns which will hurl their projectiles for miles into the air? If only one of the hundreds struck either of those vessels of yours, she would fall like a stone and be dashed to pieces on the earth. The fighting would not be all on one side.” His tone grew more and more defiant as he went on, and Alan saw that some stern lesson would be necessary to induce him to give the pledge upon which the safety of millions depended. In quiet, even tones, that contrasted strongly with those of the Moslem, he said--