In addition to the air-ship, there was a “little side invention,” as Mr. Kearns termed it, which gave that gentleman much satisfaction and comfort. The Professor dubbed it “an aërestograph,” but Kearns preferred to refer to it as “the aërial telegraph.” This latter not inaptly described it. It was an instrument fastened to the end of a support some four feet in height. Supplied each with one of these instruments, two persons many miles apart could interchange messages, without the use of any connecting wire, provided there were no interfering obstructions. The Professor referred to it as an exceedingly simple invention, based to some extent upon the same principles as those applied by Marconi, but with apparatus much simplified. One of these instruments was mounted in the room in the Chancellerie given over to Kearns; the other instrument was stored away in the air-ship. By rising in the air-ship to a sufficient altitude to clear intervening obstructions, there would thus be constant possibility of communication between the air-ship and Kearns. By means of this instrument, Kearns felt that he was at least in touch with the Professor and the news.

So matters stood on the night of the recorded conversation between the Professor and Kearns. The night was dark—slightly hazy and overcast—corresponding in many respects, as Kearns noted with joy, to the night when the previous visitation had taken place. To complete further the resemblance, a ball was being held in the Summer Palace—not upon the scale of magnificence of the preceding event, but a Court ball, nevertheless, with all the accessory brilliancy and gayety.

Shortly after midnight, the Professor, Kearns and Captain Mortimer sat watching in the room of the Chancellerie assigned to them. Immediately next to them, but separated by a solid wall, was the King’s sleeping apartment, in the antechamber of which Captain Swords was on duty as Officer of the Day.

Not long after midnight a messenger handed a note to the sentinel at the end of the corridor. It was passed on from sentinel to sentinel until it reached Captain Swords. It was a delicately perfumed little missive, addressed in a large and straggling feminine handwriting. The Captain tore it open and read:

“Captain Swords: Since you have been so inconsiderate as to be on guard to-night, you might at least send Captain Mortimer to dance one little waltz with me. He, too, seems to have disappeared. If you don’t manage this little favor for me, you need never speak to me again.

“B. C.

“P. S.—I am awfully disappointed and angry.

“P. P. S.—I may be at the entrance to the Queen’s Walk at fourteen o’clock to-morrow, but it would be no use for you to try to meet me there, because I should refuse to tell you anything interesting which might have taken place at the ball.”

Captain Swords smiled as he read, afterward standing for a moment, reflecting, with the note between his fingers. With the air of a man who has suddenly made up his mind, he left the antechamber, walked up the corridor past the King’s apartment and knocked lightly at the nearest door of the Chancellerie suite. Captain Mortimer promptly responded to the summons and a brief whispered conference took place between them. Then Captain Mortimer turned to Kearns and whispered:

“I suppose ’twouldn’t do for me to absent myself for half an hour—to go downstairs for one dance.”