This article is from the alt.usage.english FAQ, by Mark Israel misrael@scripps.edu with numerous contributions by others.
The "y" here is a representation of the obsolete letter thorn,
which looked like "b" and "p" superimposed, and was pronounced
[T] or [D] (the same as modern "th"). The pronunciation of "ye" in
"Ye Olde Curiositie Shoppe" as /ji/, which you sometimes hear, is a
spelling pronunciation.
 
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