In "Dusk," by referring to the incidents in the story, state how dusk is said to be "the hour of defeated."

The first part of this answer lies in the way that Gortsby
imagines the people who come out at the hour of dusk, which, in his mind, is a time for
those who have failed in life to emerge. Note how he describes such
failures:

Men
and women, who had fought and lost, who hid their fallen fortunes and dead hopes as far
as possible from the scrutiny of the curious, came forth in this hour of gloaming, when
their shabby clothes and bowed shoulders and unhappy eyes might pass unnoticed, or, at
any rate, unrecognised.

Dusk
then fits Gortsby's mood as he contemplates the way that others have failed in life and
then moves on to reflect on his own failure in his "subtle ambition." Of course, there
is an irony in this, as during the course of the story, Gortsby himself is shown to fail
in beign taken in by the young man and his story, and giving him some money, when at the
end the young man turns out to be a confidence trickster after all. It is therefore
appropriate that Gortsby should feel such an affinity with dusk. He has failed before,
and during the course of the story, he fails again.