"Flack," said the voices. "Flack."

An illuminating sentence floated up. "Locked himself in the attic."

Cossar was continually more wonderful. He produced great handfuls of
cotton wool and stuffed them in his ears--Bensington wondered why. Then
he loaded his gun with a quarter charge of powder. Who else could have
thought of that? Wonderland culminated with the disappearance of
Cossar's twin realms of boot sole up the central hole.

Cossar was on all fours with two guns, one trailing on each side from a
string under his chin, and his most trusted assistant, a little dark man
with a grave face, was to go in stooping behind him, holding a lantern
over his head. Everything had been made as sane and obvious and proper
as a lunatic's dream. The wool, it seems, was on account of the
concussion of the rifle; the man had some too. Obviously! So long as
the rats turned tail on Cossar no harm could come to him, and directly
they headed for him he would see their eyes and fire between them. Since
they would have to come down the cylinder of the hole, Cossar could
hardly fail to hit them. It was, Cossar insisted, the obvious method, a
little tedious perhaps, but absolutely certain. As the assistant stooped
to enter, Bensington saw that the end of a ball of twine had been tied
to the tail of his coat. By this he was to draw in the rope if it should
be needed to drag out the bodies of the rats.

Bensington perceived that the object he held in his hand was Cossar's
silk hat.

How had it got there?