For you will remember that whereas your rooms look out to the front and on to the slope of Mont Revard, Wethermill's look out over the garden and the town of Aix.

In a quarter of an hour or twenty minutes he could have reached the Villa Rose.

He could have been in the salon before half-past ten, and that is just the hour which suited me perfectly.

And, as he got out unnoticed, so he could return.

So he did return! My friend, there are some interesting marks upon the window-sill of Wethermill's room and upon the pillar just beneath it.