hn with some asperity in his tone. "What I want to
know is what all this means."

"That's exactly what I'm endeavouring to discover," said Sage evenly.
"If I were a stage detective, I should be down on my knees smelling
your carpet, or examining Pall Mall with a strong lens; but I'm not. I
never carry a magnifying-glass and I know nothing about finger-prints.
The solving of mysteries, like the detection of crime, is invariably
due to a mistake on the part of somebody who ought not to have made a
mistake."

"Then tell me how far you have got." Mr. Llewellyn John glanced across
to Colonel Walton, and was conscious of a slight knitting of his brows,
then he looked back again at Malcolm Sage, who for some moments
remained silent.

"If you were uncertain of my sanity, sir," said Sage quietly, "would
you discuss the matter with others, or would you first assure yourself
of the accuracy of your suspicions?"

He looked up suddenly, straight into Mr. Llewellyn John's eyes.

"We all know you are hopelessly and irretrievably mad, Sage," said Mr.
Llewellyn John with a smile.

"When I know definitely what has become of John Dene, I'll tell you,
sir," said Sage. "I'm not spectacular, sir. I can't deduce bigamy
from a bootlace, or murder from a meringue. I can tell you this,
however"--he paused and both his listeners leaned forward
eagerly--"that if my hypothesis is correct, the policy to pursue is to
magnify the importance of John Dene's disappearance. Incidentally," he
added, "it might result in Mr. John Dene revising his opinion of the
incapacity of British officialdom."

"Then you refuse to tell me?"

"It would be highly injudicious on my part to tell you of a mere
suspicion which might----" Malcolm Sage lifted his eye from the nail
of his left thumb, and looked straight at Mr. Llewellyn John--"which
might dictate your policy, sir."

"But the time we are wasting," protested Mr. Llewellyn John, rising and
pacing up and down impatiently.

"Nothing is lost that's wrought with tears, sir," was the enigmatical
response.

"Sage," said Mr. Llewellyn John, as he shook hands with Malcolm Sage,
"you're the most pig-headed official in the British Empire.
Chappeldale can be tiresome; but you're nothing short of an
inconvenience. Mind, Walton," he continued, turning to the chief of
Department Z., "I shall hold you responsible for Sage. If he lets me
down over this Dene business, I shall lose faith in Department Z." Th