Background on the Elocution Lesson

The sentence is from Elizabeth Von Arnim, The Enchanted April, originally published in the early 20s, lately revived by NYRB Paperbacks (but note that there is a free version on Kindle).  It's a period piece, its lyricism saved by an undercurrent of merry waspishness (Mrs. Buce reports that the film version is a good deal more anodyne).  I've been reading it aloud and I find it hard to catch her rhythm--can't make up her mind how much of it is my distance from the Edwardians, how much stylistic quirks of the author.  A few sentences--this one--strike me as downrighrt Proustian (though certainly not as elegant as Proust) in that they seem difficult to disentangle but which, once disentangled, yield up their meaning with perfect clarity.