“You see,” the captain resumed, “I have twelve numbers here on the keys of this radio-combinator—­forward, back, stop propeller motor, rudder right, rudder left, stop steering motor, light signals front, light signals rear, launch torpedoes, and so on.  The idea is that of a delayed contact.  The machinery is always ready, but it delays a few seconds until the right impulse is given, a purely mechanical problem.  I take advantage of the delay to have the message repeated by a signal back to me.  I can even change it, then.  You can see for yourself that it really takes no experience to run the thing when all is going right.  Gladys has done it frequently herself.  All you have to do is to pay attention, and press the right key for the necessary change.  It is when things go wrong that even an expert like myself—­confound it--there’s something wrong!”

The Z99 had suddenly swerved.  Captain Shirley’s brow knitted.  We gathered around closer, Gladys next to her father and leaning anxiously over the transmitting apparatus.

“I wanted to turn her to port yet she goes to starboard, and signals starboard, too.  There—­now—­she has stopped altogether.  What do you think of that?”

Gladys stroked the old seafarer’s hand gently, as he sat silently at the table, peering with contracted brows out into the now brilliantly moonlit night.

Shirley looked up at his daughter, and the lines on his face relaxed as though he would hide his disappointment from her eager eyes.

“Confound that light!  What’s the matter with it?” he exclaimed, changing the subject, and glancing up at the gas-fixture.

Kennedy had already been intently looking at the Welsbach burner overhead, which had been flickering incessantly.  “That gas company!” added the Captain, shaking his head in disgust, and showing annoyance over a trivial thing to hide deep concern over a greater, as some men do.  “I shall use the electricity altogether after this contract with the company expires.  I suppose you literary men, Mr. Jameson, would call that the light that failed.”

There was a forced air about his attempt to be facetious that did not conceal, but rather accentuated, the undercurrent of feelings in him.

“On the contrary,” broke in Kennedy, “I shouldn’t be surprised to find that it is the light that succeeded.”

“How do you mean?”

“I wouldn’t have said anything about it if you hadn’t noticed it yourself.  In fact, I may be wrong.  It suggests something to me, but it will need a good deal of work to verify it, and then it may not be of any significance.  Is that the way the Z99 has behaved always lately?”

“Yes, but I know that she hasn’t broken down of herself,” Captain Shirley asserted.  “It never did before, not since I perfected that new coherer.  And now it always does, perhaps fifteen or twenty minutes after I start her out.”

Shirley was watching the lights as they serpentined their way to us across the nearly calm water of the bay, idly toying with the now useless combinator.