Detective-Inspector Wessex arrived at about five o’clock; a quiet, resourceful man, highly competent, and having the appearance of an ex-soldier. His respect for the attainments of Paul Harley alone marked him a student of character. I knew Wessex well, and was delighted when Pedro showed him into the library.  
“Thank God you are here, Wessex,” said Harley, when we had exchanged greetings. “At last I can move. Have you seen the local officer in charge?”
 
“No,” replied the Inspector, “but I gather that I have been requisitioned over his head.”
 
“You have,” said Harley, grimly, “and over the head of the Chief Constable, too. But I suppose it is unfair to condemn a man for the shortcoming with which nature endowed him, therefore we must endeavour to let Inspector Aylesbury down as lightly as possible. I have an idea that I heard him return a while ago.”
 
He walked out into the hall to make enquiries, and a few moments later I heard Inspector Aylesbury’s voice.
 
“Ah, there you are, Inspector Aylesbury,” said Harley, cheerily. “Will you please step into the library for a moment?”
 
The Inspector entered, frowning heavily, followed by my friend.
 
“There is no earthly reason why we should get at loggerheads over this business,” Harley continued; “but the fact of the matter is, Inspector Aylesbury, that there are depths in this case to which neither you nor I have yet succeeded in penetrating. You have a reputation to consider, and so have I. Therefore I am sure you will welcome the cooperation of Detective-Inspector Wessex of Scotland Yard, as I do.”
 
“What’s this, what’s this?” said Aylesbury. “I have made no application to London.”
 
“Nevertheless, Inspector, it is quite in order,” declared Wessex. “I have my instructions here, and I have reported to Market Hilton already. You see, the man you have detained is an American citizen.”
 
“What of that?”
 
“Well, he seems to have communicated with his Embassy.” Wessex glanced significantly at Paul Harley. “And the Embassy communicated with the Home Office. You mustn’t regard my arrival as any reflection on your ability, Inspector Aylesbury. I am sure we can work together quite agreeably.”
 
“Oh,” muttered the other, in evident bewilderment, “I see. Well, if that’s the way of it, I suppose we must make the best of things.”
 
“Good,” cried Wessex, heartily. “Now perhaps you would like to state your case against the detained man?”
 
“A sound idea, Wessex,” said Paul Harley. “But perhaps, Inspector Aylesbury, before you begin, you would be good enough to speak to the constable on duty at the entrance to the Tudor garden. I am anxious to take another look at the spot where the body was found.”
 
Inspector Aylesbury took out his handkerchief and blew his nose loudly, continuing throughout the operation to glare at Paul Harley, and finally:
 
“You are wasting your time, Mr. Harley,” he declared, “as Detective-Inspector Wessex will be the first to admit when I have given him the facts of my case. Nevertheless, if you want to examine the garden, do so by all means.”
 
He turned without another word and stamped out of the library across the hall and into the courtyard.
 
“I will join you again in a few minutes, Wessex,” said Paul Harley, following.
 
“Very good, Mr. Harley,” Wessex answered. “I know you wouldn’t have had me down if the case had been as simple as he seems to think it is.”
 
I joined Harley, and we walked together up the gravelled path, meeting Inspector Aylesbury and the constable returning.
 
“Go ahead, Mr. Harley!” cried the Inspector. “If you can find any stronger evidence than the rifle, I shall be glad to take a look at it.”
 
Harley nodded good-humouredly, and together we descended the steps to the sunken garden. I was intensely curious respecting the investigation which Harley had been so anxious to make here, for I recognized that it was associated with something which he had seen from the window of Camber’s hut.
 
He walked along the moss-grown path to the sun-dial, and stood for a moment looking down at the spot where Menendez had lain. Then he stared up the hill toward the Guest House; and finally, directing his attention to the yews which lined the sloping bank:
 
“One, two, three, four,” he counted, checking them with his fingers—“five, six, seven.”
 
He mounted the bank and began to examine the trunk of one of the trees, whilst I watched him in growing astonishment.
 
Presently he turned and looked down at me.
 
“Not a trace, Knox,” he murmured; “not a trace. Let us try again.”
 
He moved along to the yew adjoining that which he had already inspected, but presently shook his head and passed to the next. Then:
 
“Ah!” he cried. “Come here, Knox!”
 
I joined him where he was kneeling, staring at what I took to be a large nail, or bolt, protruding from the bark of the tree.
 
“You see!” he exclaimed, “you see!”
 
I stooped, in order to examine the thing more closely, and as I did so, I realized what it was. It was the bullet which had killed Colonel Menendez!
 
Harley stood upright, his face slightly flushed and his eyes very bright.
 
“We shall not attempt to remove it, Knox,” he said. “The depth of penetration may have a tale to tell. The wood of the yew tree is one of the toughest British varieties.”
 
“But, Harley,” I said, blankly, as we descended to the path, “this is merely another point for the prosecution of Camber. Unless”—I turned to him in sudden excitement, “the bullet was of different—”
 
“No, no,” he murmured, “nothing so easy as that, Knox. The bullet was fired from a Lee-Enfield beyond doubt.”
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