At the end of an hour, when she happened to turn round, she saw Miss Penfold standing in the doorway.

She had not heard her footstep, and at once decided in her mind that it would be necessary to be extremely careful in her search, as at any moment Miss Penfold might look in upon her without warning.
"Have you nearly finished, Anna ?" Miss Penfold asked.
"It will take me another hour at least to dust the woodwork properly, Miss Penfold.

I have done the carpet and furniture." Miss Penfold made no remark but went away again.
"She is not likely to come back for a few minutes," Mrs.Conway said to herself.

"I think I can safely carry out one of my plans." She took from her pocket a ball of thin string, one end of which was attached to a tiny brad awl.

Going into one corner of the room she fixed the brad awl into the woodwork; then, unwinding the ball, proceeded to the other end of the room, straining the string tightly, and tied a knot to mark the length.