The shoes had
been worn by someone for whom they were too small.

Now it was clear at a glance that Manderson was always thoroughly well
shod and careful, perhaps a little vain, of his small and narrow feet.
Not one of the other shoes in the collection, as I soon ascertained,
bore similar marks; they had not belonged to a man who squeezed himself
into tight shoe-leather. Someone who was not Manderson had worn these
shoes, and worn them recently; the edges of the tears were quite fresh.

The possibility of someone having worn them since Manderson's death was
not worth considering; the body had only been found about twenty-six
hours when I was examining the shoes; besides, why should any one wear
them? The possibility of someone having borrowed Manderson's shoes and
spoiled them for him, while he was alive, seemed about as negligible.
With others to choose from he would not have worn these. Besides, the
only men in the place were the butler and the two secretaries. But I do
not say that I gave those possibilities even as much consideration as
they deserved; for my thoughts were running away with me; and I have
always found it good policy, in cases of this sort, to let them have
their heads. Ever since I had got out of the train at Marlstone early
that morning I had been steeped in details of the Manderson affair; the
thing had not once been out of my head. Suddenly the moment had come
when the daemon wakes and begins to range.

Let me put it less fancifully. After all, it is a detail of psychology
familiar enough to all whose business or inclination brings them in
contact with difficult affairs of any sort. Swiftly and spontaneously,
when chance or effort puts one in possession of the key-fact in any
system of baffling circumstances, one's ideas seem to rush to group
themselves anew in relation to that fact, so that they are suddenly
rearranged almost before one has consciously grasped the significance of
the key-fact itself. In the present instance, my brain had scarcely
formulated within itself the thought, 'Somebody who was not Manderson
has been wearing those shoes,' when there flew into my mind a flock of
ideas, all of the same character and all bearing upon this new notion.
It was unheard-of for Manderson to drink much whisky at night. It was
very unlike him to be untidily dressed, as the body was when found--the
cuffs dragged up inside the sleeves, the shoes unevenly laced; very
unlike him not to wash, when he ro