Mr. Carlyle’s groping hand sought and found a chair, on to which he dropped blankly.  His eyes were unable to detach themselves for a single moment from the very ordinary spectacle of Mr. Carrados’s mildly benevolent face, while the sterilized ghost of his now forgotten amusement still lingered about his features.

“Good heavens!” he managed to articulate, “how do you know?”

“Isn’t that what you wanted of me?” asked Carrados suavely.

“Don’t humbug, Max,” said Carlyle severely.  “This is no joke.”  An undefined mistrust of his own powers suddenly possessed him in the presence of this mystery.  “How do you come to know of Nina Brun and Lord Seastoke?”

“You are a detective, Louis,” replied Carrados.  “How does one know these things?  By using one’s eyes and putting two and two together.”

Carlyle groaned and flung out an arm petulantly.

“Is it all bunkum, Max?  Do you really see all the time—­though that doesn’t go very far towards explaining it.”

“Like Vidal, I see very well—­at close quarters,” replied Carrados, lightly running a forefinger along the inscription on the tetradrachm.  “For longer range I keep another pair of eyes.  Would you like to test them?”

Mr. Carlyle’s assent was not very gracious; it was, in fact, faintly sulky.  He was suffering the annoyance of feeling distinctly unimpressive in his own department; but he was also curious.

“The bell is just behind you, if you don’t mind,” said his host.  “Parkinson will appear.  You might take note of him while he is in.”

The man who had admitted Mr. Carlyle proved to be Parkinson.

“This gentleman is Mr. Carlyle, Parkinson,” explained Carrados the moment the man entered.  “You will remember him for the future?”

Parkinson’s apologetic eye swept the visitor from head to foot, but so lightly and swiftly that it conveyed to that gentleman the comparison of being very deftly dusted.

“I will endeavour to do so, sir,” replied Parkinson, turning again to his master.

“I shall be at home to Mr. Carlyle whenever he calls.  That is all.”

“Very well, sir.”

“Now, Louis,” remarked Mr. Carrados briskly, when the door had closed again, “you have had a good opportunity of studying Parkinson.  What is he like?”

“In what way?”

“I mean as a matter of description.  I am a blind man—­I haven’t seen my servant for twelve years—­what idea can you give me of him?  I asked you to notice.”

“I know you did, but your Parkinson is the sort of man who has very little about him to describe.  He is the embodiment of the ordinary.  His height is about average——­”

“Five feet nine,” murmured Carrados.  “Slightly above the mean.”

“Scarcely noticeably so.  Clean-shaven.  Medium brown hair.  No particularly marked features.  Dark eyes.  Good teeth.”

“False,” interposed Carrados.  “The teeth—­not the statement.”