Thorndyke remained silent for a while, pacing slowly along the gravel path, with his eyes bent on the ground:  not abstractedly, however, but with a searching, attentive glance that roved amongst the shrubs and bushes, as though he were looking for something.

“What sort of man,” he asked presently, “is this Leonard Wolfe?  Obviously he is a low scoundrel, but what is he like in other respects?  Is he a fool, for instance?”

“Not at all, I should say,” said Mr. Curtis.  “He was formerly an engineer, and, I believe, a very capable mechanician.  Latterly he has lived on some property that came to him, and has spent both his time and his money in gambling and dissipation.  Consequently, I expect he is pretty short of funds at present.”

“And in appearance?”

“I only saw him once,” replied Mr. Curtis, “and all I can remember of him is that he is rather short, fair, thin, and clean-shaven, and that he has lost the middle finger of his left hand.”

“And he lives at?”

“Eltham, in Kent.  Morton Grange, Eltham,” said Mr. Marchmont.  “And now, if you have all the information that you require, I must really be off, and so must Mr. Curtis.”

The two men shook our hands and hurried away, leaving Thorndyke gazing meditatively at the dingy flower-beds.

“A strange and interesting case, this, Jervis,” said he, stooping to peer under a laurel-bush.  “The inspector is on a hot scent—­a most palpable red herring on a most obvious string; but that is his business.  Ah, here comes the porter, intent, no doubt, on pumping us, whereas—­” He smiled genially at the approaching custodian, and asked:  “Where did you say those houses fronted?”

“Cotman Street, sir,” answered the porter.  “They are nearly all offices.”

“And the numbers?  That open second-floor window, for instance?”

“That is number six; but the house opposite Mr. Hartridge’s rooms is number eight.”

“Thank you.”

Thorndyke was moving away, but suddenly turned again to the porter.

“By the way,” said he, “I dropped something out of the window just now—­a small flat piece of metal, like this.”  He made on the back of his visiting card a neat sketch of a circular disc, with a hexagonal hole through it, and handed the card to the porter.  “I can’t say where it fell,” he continued; “these flat things scale about so; but you might ask the gardener to look for it.  I will give him a sovereign if he brings it to my chambers, for, although it is of no value to anyone else, it is of considerable value to me.”

The porter touched his hat briskly, and as we turned out at the gate, I looked back and saw him already wading among the shrubs.

The object of the porter’s quest gave me considerable mental occupation.  I had not seen Thorndyke drop any thing, and it was not his way to finger carelessly any object of value.  I was about to question him on the subject, when, turning sharply round into Cotman Street, he drew up at the doorway of number six, and began attentively to read the names of the occupants.