Kennedy started the phonograph, running it along, stopping it, taking up the record at a new point.

“Listen,” he exclaimed at length, “there’s something interesting, the WXY call—­Seaville station—­from some one on the Lucie only a few minutes ago, sending a message to be relayed by Seaville to the station at Beach Park.  It seems impossible, but buzzing and ticking forth is this message from some one off this very houseboat.  It reads:  “Miss Valerie Fox, Beach Park.  I am suspected of the murder of Mrs. Edwards.  I appeal to you to help me.  You must allow me to tell the truth about the messages I intercepted for Mrs. Edwards which passed between yourself on the ocean and Mr. Edwards in New York via Seaville.  You rejected me and would not let me save you.  Now you must save me.”

Kennedy paused, then added, “The message is signed by Dr. Jermyn!”

At once I saw it all.  Jermyn had been the unsuccessful suitor for Miss Fox’s affections.  But before I could piece out the rest of the tragic story, Kennedy had started the phonograph record at an earlier point which he had skipped for the present.

“Here’s another record—­a brief one—­also to Valerie Fox from the houseboat:  ’Refuse all interviews.  Deny everything.  Will see you as soon as present excitement dies down.’”

Before Kennedy could finish, Waldon had leaped forward, unable longer to control his feelings.  If Kennedy had not seized his arm, I verily believe he would have cast Dr. Jermyn into the bay into which his sister had fallen two nights before in her terribly weakened condition.

“Waldon,” cried Kennedy, “for God’s sake, man—­wait!  Don’t you understand?  The second message is signed Tracy Edwards.”

It came as quite as much a shock of surprise to me as to Waldon.

“Don’t you understand?” he repeated.  “Your sister first learned from Dr. Jermyn what was going on.  She moved the Lucie down here near Seaville in order to be near the wireless station when the ship bearing her rival, Valerie Fox, got in touch with land.  With the help of Dr. Jermyn she intercepted the wireless messages from the Kronprinz to the shore—­between her husband and Valerie Fox.”

Kennedy was hurrying on now to his irresistible conclusion.  “She found that he was infatuated with the famous stage beauty, that he was planning to marry another, her rival.  She accused him of it, threatened to defeat his plans.  He knew she knew his unfaithfulness.  Instead of being your sister’s murderer, Dr. Jermyn was helping her get the evidence that would save both her and perhaps win Miss Fox back to himself.”

Kennedy had turned sharply on Edwards.

“But,” he added, with a glance that crushed any lingering hope that the truth had been concealed, “the same night that Dr. Jermyn arrived here, you visited your wife.  As she slept you severed the nerves that meant life or death to her.  Then you covered the cuts with the preparation which you knew Dr. Jermyn used.  You asked him to stay, while you went away, thinking that when death came you would have a perfect alibi—­perhaps a scapegoat.  Edwards, the radio detective convicts you!”