On 2008-02-12 16:49, Patrick Ryan wrote:
> Let us assume that a given *a: in PIE was pre-PIE *a. Could you give me an
> idea of what process could lengthen it? - vrdhi will, of course, not be
> supremely convincing.
I think it was a purely phonetic process, and a fairly natural one.
Other things being equal, low vowels tend to be longer than high or mid
ones. Even in US English the vowels of <god>, <long> (if different from
the preceding one) and <bad>, though phonologically patterning with
"short/lax" vowels, are quite long phonetically and are easily tensed in
favourable environments. The first two may occur in "free" positions
(without a following consonant, as in <bra> and <law>.
Piotr