In the Tom Swift and Nancy Drew books I've been devouring lately, there're all sorts of references to "trained" nurses. As in, a *trained* nurse puts a chair beside the bed in the hospital for Tom Swift, then smiles at him with her "even, white teeth".
I've got to assume two things from this: that the mention of *training* meant something to people in pre-1950's America, perhaps that "trained nurse" differentiated a person from a sort of "sitter" or "companion", and second, that the state of dentistry and orthodontia must've been so bad that even, white teeth rated a mention of their own.
Goodness. What a sentence.
Or maybe there were packs, nay herds, of untrained nurses darkening the plains of the American west before 1930. The solitary, laconic nurse-herders drove them from the desolate deserts to Chicago, where, with the help of starch and a horsewhip, they were transformed into Trained Nurses.
I kinda like that second theory.