Q said "In one of Shakespeare's plays, there is a reference to 'woolen' pipes"

Taking into account the path that the written (many and various) versions (and "corrected versions") of his plays have taken thru history to get to us with the enormous amount of misprintings, misreadings when setting up printers type, change of spellings, phoenetic spellings, spellings were variable, even by a person spelling his own name at times, the fact that "English Spelling" was not a "Standardised" thing until the 18-19th C...

W i.e. "double u" could easily have been an attempt to write "UU" instead of "W" thus the "Wah" sound possibly should have been read as nearer "eeooo"...

thus "uuoolen" - which to my cloth ears sounds remarkably close... what with several hundred years and all.....

:-)

Robin