"This gets me well out of my depth, Mr. Addison," said Inspector Gatton.
 
We were standing in the garden at a point near to my open study window. A small flower-bed intervened between the path and the high privet hedge. It lay much in shade, and Coates had set tobacco plants there. But the soil was softer here than elsewhere.
 
Clearly marked upon it were the imprints of little high-heeled shoes.
 
"It seems to take us back to the days of 'Spring-heeled Jack,'" my friend continued; "which was before my time! I don't think that mystery was ever cleared up?"
 
"No," I replied, meeting his questioning glance; "it never was, satisfactorily. Therefore the analogy is an unfortunate one. But as you say, it certainly looks as though my visitor had sprung across a six-foot hedge!"
 
"It's absolutely mad," said Gatton gloomily. "Far from helping us, it only plunges us deeper in the mire."
 
We returned to the study, and:
 
"You will have seen the daily papers?" asked the Inspector.
 
I nodded.
 
"Practically all of them. They give a hateful prominence to the name of Miss Merlin."
 
"And to that of the new baronet—Sir Eric," said Gatton significantly.
 
I stared at him straightly.
 
"Do you seriously believe," said I, "that Eric Coverly had anything whatever to do with the death of his cousin?"
 
Gatton stirred uneasily in his chair.
 
"Well," he answered, "ignoring everything else for the moment, who else benefits by Sir Marcus Coverly's death?"
 
It was a poser—a question which I had dreaded because I had known it to be unanswerable.
 
"He inherits the title," continued Gatton, "and on the death of Lady Burnham Coverly he inherits Friars' Park. There is some clause or entail, or legal hotchpotch whereby the estate and revenue remain hers during her lifetime."
 
"But I understand the estate is mortgaged?"
 
"That I have to confirm, Mr. Addison," replied Gatton. "Sir Eric's solicitor has no information on the point and that of Sir Marcus's man of business is inexact. But even supposing that only the title is concerned, many a man has lost his life for less. Then you have to consider—Miss Merlin."
 
"In what way?" I demanded
 
"In relation to the attitude of Sir Marcus. Jealousy makes men (and women) do strange and desperate things. The character of Eric Coverly, the new baronet, is a very odd one."
 
"He is headstrong and in some respects weak," I admitted. "But otherwise he is an ordinary English gentleman, with the traditions of an old name and a public school to back him up. I tell you, Gatton, it's nonsense. His army career alone shows him to be a sound man."
 
"Yes," murmured Gatton; "he was awarded a decoration for distinguished service in Egypt."
 
That seemingly simple remark struck me with all the force of a physical blow. Gatton began quietly to load his pipe, without even glancing in my direction; but the covert significance of his words was all too apparent:
 
"Gatton," I said—"what the devil are you driving at?"
 
He slightly shrugged his shoulders.
 
"What you may term the hocus-pocus side of the case," he replied, "turns on matters Egyptian, doesn't it? Very well. Who else, that we know about, is associated, or ever has been associated with Egypt?"
 
"But—the woman?"
 
"Ah!" said Gatton. "Now you are getting down to the depths. But assuming that the extraordinary characteristics of this visitor of yours can be explained in some way, by deliberate trickery, for example, might she not be a woman whom Eric Coverly met in Egypt?"
 
I stared silently a while, and then:
 
"In short, a rival of Miss Merlin's?" I suggested.
 
"Precisely. The trick with the photograph was just of the kind one would expect from a madly jealous woman. Everything planned with supreme cunning, but the scene at which the hated rival enters the scheme badly overdone."
 
"And you believe Coverly's silence to be due to the fact that he is shielding some one?"
 
"Well, that or shielding himself. What else can it mean? A man suspected of murder doesn't hesitate to establish an alibi unless he is in a desperately tight corner. The exact position of your strange-eyed acquaintance in the case is not apparent to me at the moment, I'll admit, but I seem to have heard that there have been rare instances of human beings with luminous eyes."
 
"Quite right, Inspector," I agreed; "I hope very shortly to have some further particulars for you bearing upon this point. I am endeavoring to obtain a work by Saint-Hilaire dealing with teratology."
 
"As to her extraordinary activity and agility," Gatton continued, "we must remember that a privet hedge is not like a stone wall. I mean she may not have actually cleared the whole six feet, and after all, this is the age of the athletic girl. There are women athletes who can perform some extraordinary feats of high-jumping. Of course, there are still a number of witnesses to be discovered and examined, but I know by now exactly what to expect. It's an ingenious idea, although not entirely new to me.
 
"The whole thing has been managed by means of the telephone—a powerful ally of the modern criminal. Briefly what happened was this: The Red House—selected because of its lonely position, but also because it was fairly accessible—was leased by our missing assassin without any personal interview taking place. We have to look then in the first instance for some one possessing considerable financial resources. It was by the effective substitution of a year's rent—in cash—for the more usual references, that our man—or woman—whom I will call 'A' secured possession of the keys and right of entry to the premises. A limited amount of furniture was obtained in the same manner. We haven't found the firm who supplied it, but I don't doubt that the business was done over the telephone, cash being paid as before. Duplicate keys must have been made for some of the doors, I think—a simple matter. We shall find that the furnishing people as well as the caterer who later on supplied the supper were admitted to the Red House by a district messenger or else had the keys posted to them for the purpose.
 
"The whole business was built up around a central idea, simple in itself: that of inveigling Sir Marcus into the prepared supper-room. His attendance at the New Avenue Theater last night was doubtless assured—although we may never prove it—by another of these mysterious telephone messages, probably purporting to come from Miss Merlin. The cold-blooded thoroughness with which 'A' arranged for a crate to be delivered at the garage and for the body of the murdered man to be taken to the docks and shipped to the West Indies, illuminates the character of the person we have to seek.
 
"Discovery sooner or later was inevitable, of course. It came sooner because of the accident at the docks. Had it come later I don't doubt that 'A' would have dismantled the Red House again so that the investigation would have been severely handicapped. As it is, the only dismantling done was the most important of all."
 
"You mean?" I said with keen interest.
 
"The death-machine," answered Gatton. "The cunning device around which all these tra............