is a very important point. The presumption is that it was within
a few minutes afterwards. The cards still lay upon the table.
It was already past their usual hour for bed. Yet they had not
changed their position or pushed back their chairs. I repeat,
then, that the occurrence was immediately after his departure,
and not later than eleven o'clock last night.

"Our next obvious step is to check, so far as we can, the
movements of Mortimer Tregennis after he left the room. In this
there is no difficulty, and they seem to be above suspicion.
Knowing my methods as you do, you were, of course, conscious of
the somewhat clumsy water-pot expedient by which I obtained a
clearer impress of his foot than might otherwise have been
possible. The wet, sandy path took it admirably. Last night was
also wet, you will remember, and it was not difficult--having
obtained a sample print--to pick out his track among others and
to follow his movements. He appears to have walked away swiftly
in the direction of the vicarage.

"If, then, Mortimer Tregennis disappeared from the scene, and yet
some outside person affected the card-players, how can we
reconstruct that person, and how was such an impression of horror
conveyed? Mrs. Porter may be eliminated. She is evidently
harmless. Is there any evidence that someone crept up to the
garden window and in some manner produced so terrific an effect
that he drove those who saw it out of their senses? The only
suggestion in this direction comes from Mortimer Tregennis
himself, who says that his brother spoke about some movement in
the garden. That is certainly remarkable, as the night was
rainy, cloudy, and dark. Anyone who had the design to alarm