That meant, no doubt, that Mr.Sleuth would pass the rest of the evening in the cheerless room above.

He hadn't spent any time up there for quite a long while--in fact, not for nearly ten days.

'Twas odd he chose to-night, when it was so foggy, to carry out an experiment.
She groped her way to a chair and sat down.

She felt very tired-- strangely tired, as if she had gone through some great physical exertion.
Yes, it was true that Mr.Sleuth had brought her and Bunting luck, and it was wrong, very wrong, of her ever to forget that.
As she sat there she also reminded herself, and not for the first time, what the lodger's departure would mean.

It would almost certainly mean ruin; just as his staying meant all sorts of good things, of which physical comfort was the least.