“We’ve got to be careful, certainly,” said Colton; “but I think if we can capture Whalley, we’ll have no more mysterious killings.”

“Oh, that does very well in part; but it doesn’t fill out the requirements,” said the reporter impatiently. “Now, I’m going to run over my notes briefly, and if anyone can add anything, speak up. First, the killing of the seaman, Petersen, on the night of the shipwreck. That was on the thirteenth, an uncanny date, sure enough. Next, the killing of the sheep by the same wound, on the fourteenth, and on the same evening Professor Ravenden’s experience with some threatening object overhead.”

“Pardon me; I did not ascribe any threatening motive or purpose to the manifestation,” put in the professor. “Indeed, if I may challenge your memory, I suggested an air-ship. It seems that the unhappy aero-expert’s kites well may have been the source of the sound I heard.”

“Let us assume so for the present. Next we come to Mr. Colton’s encounter and the death of the mare on the evening of the fifteenth.”

“The kites again, of course,” said Everard. “Even allowing that—and I expect to get conclusive proof against it later—what, then, chased the animal over the cliff?”

“Maybe the kites came down later and blew along the ground after her. If you were a horse, and a string of six-foot kites came bounding along in the darkness after you, wouldn’t you jump a cliff?”

“Ask Professor Ravenden,” suggested Haynes maliciously.

“The jest is not an unfair one,” said the scientist good-humouredly. “I fear that I should.”

“Charge the death of the mare to the kites, then. Pity we can’t lay the sheep to their account too. The third count against them is Professor Ravenden’s adventure of the eighteenth, and the death of the aeronaut. As to Professor Ravenden’s part, there remains to be explained the cutting of the kite strings, if they were cut.”

“That must have been done, it would seem, in mid-air, just as Petersen the sailor was killed,” said Dick Colton.