Aside from description, what other mode of development is implicitly part of the structure of "Once More to the Lake"?

"Once More to the Lake" is structured as a chronological
narrative; it is developed with passages of exposition as White compares and contrasts
the lake he visits with his young son with the lake he remembers from his own youth.
White observes many similarities; much of what he sees and experiences seems not to have
changed since he had been there as a boy. Fishing, going to the farmhouse for dinner,
and an afternoon thunderstorm all seem the same as he remembers. The sense that nothing
has changed comforts him.

However, throughout the essay the
comforting comparisons are juxtaposed with disconcerting contrasts. The dirt path
leading to the farmhouse is different; the tracks of the horses' hooves that White
remembers from his youth are gone now; only tire tracks from motorized vehicles are
visible. He also notices a disconcerting difference in one specific element of the
lake's environment:

readability="20">

The only thing that was wrong now, really, was
the sound of the place, an unfamiliar nervous sound of the outboard motors. This was the
note that jarred, the one thing that would sometimes break the illusion and set the
years moving. In those other summertimes, all motors were inboard; and when they were at
a little distance, the noise they made was a sedative, an ingredient of summer sleep . .
. But now the campers all had outboards. In the daytime, in the hot mornings, these
motors made a petulant, irritable sound; at night, in the still evening when the
afterglow lit the water, they whined about one's ears like
mosquitoes.

It is these
expository passages of contrast that finalize the theme of the narrative: despite the
illusion of sameness, of timelessness, White sometimes feels during his visit to the
lake with his son, things have changed because time has not stood
still.