First Period First Narrative - Chapter XVIII

"The mystery in that quarter is thicker than ever," he said. "I have
traced her to a shop at Frizinghall, kept by a linen draper named
Maltby. She bought nothing whatever at any of the other drapers' shops,
or at any milliners' or tailors' shops; and she bought nothing at
Maltby's but a piece of long cloth. She was very particular in
choosing a certain quality. As to quantity, she bought enough to make a
nightgown."

"Whose nightgown?" I asked.

"Her own, to be sure. Between twelve and three, on the Thursday morning,
she must have slipped down to your young lady's room, to settle the
hiding of the Moonstone while all the rest of you were in bed. In going
back to her own room, her nightgown must have brushed the wet paint
on the door. She couldn't wash out the stain; and she couldn't safely
destroy the night-gown without first providing another like it, to make
the inventory of her linen complete."

"What proves that it was Rosanna's nightgown?" I objected.

"The material she bought for making the substitute dress," answered the
Sergeant. "If it had been Miss Verinder's nightgown, she would have had
to buy lace, and frilling, and Lord knows what besides; and she wouldn't
have had time to make it in one night. Plain long cloth means a plain
servant's nightgown. No, no, Mr. Betteredge--all that is clear enough.
The pinch of the question is--why, after having provided the substitute
dress, does she hide the smeared nightgown, instead of destroying it?
If the girl won't speak out, there is only one way of settling the
difficulty. The hiding-place at the Shivering Sand must be searched--and
the true state of the case will be discovered there."