On 2008-06-08 15:25, Patrick Ryan wrote:
> We are all familiar with many examples like:
>
> cónvert, noun; convért, verb.
>
> I am wondering how far back this pattern of stress-accent differentiation
> can be traced?
Not _very_ far: to Early Modern English, with a lot of vacillation and
unsteadily increasing productivity in more recent times. The difference
is the result of more-or-less obligatory stress retraction in
(Franco-)Latinate nouns (as opposed to verbs and adjectives). I would
attribute the difference to the fact that verbs, when inflected, often
receive an extra syllable ([convert]ing, [convert]ed, formerly also inf.
[convert]e(n), 3sg. [convert]eth, 2sg. [convert]est); adjectives like
<converse> are associated with adverbs in -ly ([converse]ly); and in
both cases the unstressed final syllable protects the penult stress from
shifting. Borrowed nouns with more than one full vowel seem to have had
variable stress in Middle English (though poets like Chaucer used the
iambic variant mostly in line-final positions; cf. Mod.E bamBOO, but
BAMboo FURniture, depending on the rhythmic environment), and even now
the second syllable usually has a full vowel (like that of the
final-stressed verb). But denominative verbs like <to comfort> are
trochaic, not iambic, and completely homophonous with the nouns they are
derived from.
Piotr