telephoning by the open window, with the lights on,
and the drinks on the table; is that it?"

"That is so, Mr. Murch." The delicacy of the change in Martin's manner
when called upon to answer the detective momentarily distracted Trent's
appreciative mind. But the big man's next question brought it back to
the problem at once.

"About those drinks. You say Mr. Manderson often took no whisky before
going to bed. Did he have any that night?"

"I could not say. The room was put to rights in the morning by one of
the maids, and the glass washed, I presume, as usual. I know that the
decanter was nearly full that evening; I had refilled it a few days
before, and I glanced at it when I brought the fresh syphon, just out of
habit, to make sure there was a decent-looking amount."

The inspector went to the tall corner-cupboard and opened it. He took
out a decanter of cut glass, and set it on the table before Martin. "Was
it fuller than that?" he asked quietly. "That's how I found it this
morning." The decanter was more than half empty.

For the first time Martin's self-possession wavered. He took up the
decanter quickly, tilted it before his eyes, and then stared amazedly at
the others. He said slowly: "There's not much short of half a bottle
gone out of this since I last set eyes on it--and that was Sunday
night."

"Nobody in the house, I suppose--" suggested Trent discreetly.

"Out of the question," replied Martin briefly. Then he added: "I beg
pardon, sir, but this is a most extraordinary thing to me. Such a thing
never happened in all my experience of Mr. Manderson. As for the
women-servants, they never touch anything. I can answer for it; and as
for me, when I want a drink I can help myself without going to the
decanters." He took up the decanter again, and aimlessly renewed his
observation of the contents, while the inspector eyed him with a look of
serene satisfaction, as a master contemplates his handiwork.

Trent turned to a fresh page of his notebook, and tapped it thoughtfully
with his pencil. Then he looked up and said: "I suppose Mr. Manderson
had dressed for dinner that night."

"Certainly, sir. He had on a suit with a dress-jacket, what he used to
refer to as a Tuxedo, which he usually wore when dining at home or
informally."

"And he was dressed like that when you saw him last?"

"All but the jacket, sir. When he spent the evening in the library, as
usually happened, he would change it for an old sh