Query: "grown" with two syllables, what's its history?

[Lyle Campbell]

        In the Origins of New Zealand English Project are are investigating
words with the past participle shape of -own, as in 'known',
'grown', 'shown', 'blown', etc. In New Zealand some pronounce these as two
syllables, e.g. 'grow-en' [schwa in second] in contrast to, for example,
monosyllabic 'groan', whereas for others both are monosyllabic.  At present
it seems that the population is fairly evenly divided between those who use
a
monosyllabic pronunciation and those who use a disyllabic pronunciation,
with no detectible sociolinguistic correlations with age, sex, social
class, etc., and the population seems to be about equally divided in their
view as
to which is the "correct" version.
        Question:  We would like to know the 2-syllable version is attested
in other varieties of English elsewhere and whether anyone knows of any
historical information about these forms which could throw some light on
their history here in NZ. Thanks in advance, Elizabeth Gordon, Margaret
Maclagan, and Lyle Campbell
        Please send replies to:  e.gordon at ling.canterbury.ac.nz (Elizabeth
Gordon)
Dept of Linguistics
University of Canterbury,
Christchurch, New Zealand
 
 
Lyle Campbell
Dept. of Linguistics
University of Canterbury
Private Bag 4800
Christchurch, New Zealand
Fax:   64-3-364-2065
Phone: 64-3-364-2242