Compare the writing style of Hector Munro in "Dusk" and O. Henry in "Gift of the Magi."

In addition to the similar use of irony and point of view
as mentioned above, there is in both Saki's "Dusk" and O. Henry's "Gift of the Magi" the
surprise ending which results from the characters' misperceptions and assumptions about
others. 

In "Dusk," for instance, Norman Grotsky, who sits
on the bench at the park on Hyde Park Corner, assumes that all who come there seek
anonymity as they have somehow been defeated in life.  But, of course, he has misjudged
the old man at the end of the bench who bought the cake of soap.  Similarly, Della and
Jim have assumed a pre-existing condition with each other which allows them to make the
decision to buy the gifts that they have.  They, too, underestimate others; they
underestimated the love that their spouse had for them.