David Stifter wrote:
> In all likelihood the length opposition was neutralised in the first
> vowels in hiatuses. I am not aware of any way to distinguish between
> long and short in that position (but if somebody knows a criterium,
> I'd be glad to know).
Rhyme could show it, if there are any pertinent examples. If we had an
old poem where 'toir' rhymed with, say, a compound like 'so-fhir' (good
men), that would suggest that the 'o' was short.