The prince strode restlessly away a few paces, then returned.  “Were you ever at sea before?”

“I once owned a y——­” Mr. Heatherbloom paused—­with an effort resumed his part and a smile somewhat strained:  “I once went on a cruise on a gentleman’s yacht.”  Some one was in the state-room; was overhearing.  His head hummed; the refrain of the taut lines rang louder.

“What as?  Cabin-boy, cook?”

“Why, you see—­” The prince certainly did not see him—­he was once more staring away, over the dark water—­“I acted in a good many capacities.  Kind of general utility, as it were.  Doing this, that, and the other!”

“‘The other’, I should surmise.”  Contemptuously.

Mr. Heatherbloom moved; the curtain had moved again.  “Where are you going?” he asked a little wildly.  “You see I might have important business on shore.”  Foolish talk,—­yet it fitted in as well as anything.

The prince, for his part, did not at first seem to catch the other’s words; when he did he laughed loudly, sardonically.  “That is good; excellent! You have ’important business’!”

“Yes; important,” repeated Mr. Heatherbloom.  “I—­” He got no further.  His eyes met another’s at the window, rested a moment on a woman’s face which then suddenly vanished.  But not before he realized that she, too, had seen him—­seen and recognized.  He had caught in that fleeting instant, wonder, irony, incredulity—­a growing understanding!  Then he heard a soft laugh—­a musical but devilish laugh—­Sonia Turgeinov’s!

CHAPTER XV

THE SWORD OF DAMOCLES

Mr. Heatherbloom stood as if stunned, his face very pale.  For the instant all his suppressed emotion concentrated on this woman—­his evil genius—­who had betrayed him before and who would betray him again, now.  He waited, breathing hard.  Why did she not appear?  Why did not the blow fall?  He could not understand that interval—­nothing happening.  Was she but playing with him?  The prince had abruptly turned; apparently he had not heard that very low laugh.  Bored, no doubt, by the interview, he had started to walk away, almost at the same time Mr. Heatherbloom had caught sight of the face at the window.  As in a dream Mr. Heatherbloom now heard his excellency’s brusk voice addressing a command to the officer, listened to the latter a moment or two later, addressing him.

“Come along!” The officer’s English was labored and guttural.

Mr. Heatherbloom’s eyes swung swiftly from the near-by door through which he had momentarily expected the woman to emerge.  Involuntarily he would have stepped after the vanishing figure of the prince—­what to do, he knew not, when—­