The novel is written in roving omniscient -- God's point of view-- and here, p, 60, that tone comes through resoundingly.
"It was that time before a formal dinner when the assembled guests refrain from beginning a long conversation, expecting to be called to the hors d'oevres, but at the same time consider it necessaru to move about and not be silent, in order to show that they are not at all impatient to sit down at the table."
Telling the truth with the fiction: that's one example. Novelist as sociologist. More about that anon.
I was so charmed by the descriptions of the dinner, e.g.,:
"The countess, too, from behind the pineapples, neve forgetting her duties as hostess, cast meaningful glances at her husband, the redness of whose face and bald head, it seemed to her, constrasted sharply with his gray hair."
What strikes me is "from behind the pineapples"-- for, a writer could take that and vary it and end up with a picture of a hostess at her table (and a visual sense of depth) in an infinite variety of settings, e.g.,
"from behind the open box of Cheerios"
"from behind the beeswax tapers in their porcelain holders"