However, I was too much frightened by the episode of the cheque to say anything of my nascent suspicions to Charles.  I waited rather to see how events would shape themselves.

After a while Medhurst’s vigilance grew positively annoying.  More than once he came to Charles with reports and shorthand notes distinctly distasteful to my excellent brother-in-law.  “The fellow is getting to know too much about us,” Charles said to me one day.  “Why, Sey, he spies out everything.  Would you believe it, when I had that confidential interview with Brookfield the other day, about the new issue of Golcondas, the man was under the easy-chair, though I searched the room beforehand to make sure he wasn’t there; and he came to me afterwards with full notes of the conversation, to assure me he thought Brookfield—­whom I’ve known for ten years—­was too tall by half an inch to be one of Colonel Clay’s impersonations.”

“Oh, but, Sir Charles,” Medhurst cried, emerging suddenly from the bookcase, “you must never look upon any one as above suspicion merely because you’ve known him for ten years or thereabouts.  Colonel Clay may have approached you at various times under many disguises.  He may have built up this thing gradually.  Besides, as to my knowing too much, why, of course, a detective always learns many things about his employer’s family which he is not supposed to know; but professional honour and professional etiquette, as with doctors and lawyers, compel him to lock them up as absolute secrets in his own bosom.  You need never be afraid I will divulge one jot of them.  If I did, my occupation would be gone, and my reputation shattered.”

Charles looked at him, appalled.  “Do you dare to say,” he burst out, “you’ve been listening to my talk with my brother-in-law and secretary?”

“Why, of course,” Medhurst answered.  “It’s my business to listen, and to suspect everybody.  If you push me to say so, how do I know Colonel Clay is not—­Mr. Wentworth?”

Charles withered him with a look.  “In future, Medhurst,” he said, “you must never conceal yourself in a room where I am without my leave and knowledge.”

Medhurst bowed politely.  “Oh, as you will, Sir Charles,” he answered; “that’s quite at your own wish.  Though how can I act as an efficient detective, any way, if you insist upon tying my hands like that, beforehand?”

Again I detected a faint American flavour.

After that rebuff, however, Medhurst seemed put upon his mettle.  He redoubled his vigilance in every direction.  “It’s not my fault,” he said plaintively, one day, “if my reputation’s so good that, while I’m near you, this rogue won’t approach you.  If I can’t catch him, at least I keep him away from coming near you!”

A few days later, however, he brought Charles some photographs.  These he produced with evident pride.  The first he showed us was a vignette of a little parson.  “Who’s that, then?” he inquired, much pleased.