>>I guess any language and its vocabulary will grow and develop, but the key here is that the pronounciation itself had shifted.<<
David,
that strikes me as really strange! Does anyone from anywhere know of this having happened with English--on a
wide-spread basis, that is? I know that regional dialects
change pronunciation (good heavens! I first typed that as
"pornunciation"--gives rise to all kinds of possibilities,
doesn't it??) from place to place: for ex., some in the
U.S. South say IN-sur-ance, and people in the rest of
the country, as far as I know, say in-SUR-ance.
But, thinking back to adult conversations that I heard as
a child, I can't tell any major differences from today.

I wonder what the cause of this was? Societal change in
some specific way? I will hazard a guess that it is
possible that someone who was born or grew up around 1900
might have been taught the old language of the aristocrats, if his or her grandparents had anything to do with it.
Then during the changes wrought by the industrial revolution, this way of speaking became frowned on? A hundred and fifty year late "liberte, egalite, fraternite"?