Mr. Trevor cleared his throat again. 
“Discretion is always to be observed, Mr. Drew.  And I, who have been in
the public service, know the full value of it.”

Mr. Trevor leaned forward, at the same time glancing anxiously up at the tree, for fear, perhaps, that Mr. Cooke might be concealed therein.  He said in a stage whisper: 

“A criminal is concealed on this island.”

Drew started perceptibly.

“Yes,” said Mr. Trevor, with a glance of triumph at having produced an impression on a detective, “I thought it my duty to inform you.  He has been hidden by the followers of the unscrupulous person I referred to, in a cave, I believe.  I repeat, sir, as a man of unimpeachable standing, I considered it my duty to tell you.”

“You have my sincere thanks, Mr. Trevor,” said Drew, holding out his hand, “and I shall act on the suggestion.”

Mr. Trevor clasped the hand of the detective, and they returned quietly to their respective tents.  And in course of time I followed them, wondering how this incident might affect our morning’s expedition.

CHAPTER XIV

My first thought on rising was to look for the detective.  The touch of the coming day was on the lake, and I made out the two boats dimly, riding on the dead swell and tugging idly at their chains.  The detective had been assigned to a tent which was occupied by Mr. Cooke and the Four, and they were sleeping soundly at my entrance.  But Drew’s blankets were empty.  I hurried to the beach, but the Scimitar’s boat was still drawn up there near the Maria’s tender, proving that he was still on the island.

Outside of the ladies’ tent I came upon Miss Thorn, stowing a large basket.  I told her that we had taken that precaution the night before.

“What did you put in?” she demanded.

I enumerated the articles as best I could.  And when I had finished, she said,

“And I am filling this with the things you have forgotten.”

I lost no time in telling her what I had overheard the night before, and that the detective was gone from his tent.  She stopped her packing and looked at me in concern.

“He is probably watching us,” she said.  “Do you think we had better go?”

I thought it could do no harm.  “If we are followed,” said I, “all we have to do is to turn back.”

Miss Trevor came out as I spoke, and our conductor appeared, bending under the hamper.  I shouldered some blankets and the basket, and we started.  We followed a rough path, evidently cut by a camping party in some past season, but now overgrown.  The Fraction marched ahead, and I formed the rear guard.  Several times it seemed to me as though someone were pushing after us, and more than once we halted.  I put down the basket and went back to reconnoitre.  Once I believed I saw a figure flitting in the gray light, but I set it down to my imagination.