Annie racked her brains in vain.

"I'm sorry, sir, but it's clean gone. I don't think I can have
noticed it."

"It does not matter," said Poirot, not betraying any sign of
disappointment. "Now I want to ask you about something else.
There is a saucepan in Mrs. Inglethorp's room with some coco in
it. Did she have that every night?"

"Yes, sir, it was put in her room every evening, and she warmed
it up in the night--whenever she fancied it."

"What was it? Plain coco?"

"Yes, sir, made with milk, with a teaspoonful of sugar, and two
teaspoonfuls of rum in it."

"Who took it to her room?"

"I did, sir."

"Always?"

"Yes, sir."

"At what time?"

"When I went to draw the curtains, as a rule, sir."