From Alan James – 25 July 2020
According to Ronald Black, ‘ao’ is pronounced with the back of the tongue raised, as for [o], the lips spread as for [e]. I agree that modern Sottish Gaelic speakers do pronounce it as a rather higher vowel, so more like tongue [u], lips [i], so it can sound a bit like ‘oo’ to English ears. But the medieval scribes had good ears and were right to hear it as a combination of [e] and [o]. German ‘ö’ conversely is pronounced with the front of the tongue raised as for [e], but the lips rounded as for [o], but the resultant sound is pretty similar. In Irish, it’s become a purely front vowel, [i:], and that seems to be reflected in some parts of Scotland (e.g. Crieff), but in Galloway it seems to have kept its [o]/[u] character.
You’re right that ‘oo’ is not commonly used in Older/ Middle Scots orthography. In Middle English if would represent long [o:], but Scots (somewhat confusingly) sometimes used ‘oi’ for long [o:]. But I think you’re thinking of long [u:] (‘oo’ in Modern English spelling), if they were marking the length, that was ‘ui’.
I think Cruffock has a short first vowel, like fuffock or Suffolk? That must have been shortened in Scots, it was probably adopted early.
Pretty well all the forms we’re discussing show that in Galloway ‘bh’ between vowels had become [ṷ] (i.e. approaching [w]) which would have been absorbed by the preceding vowel in words like craobhach, riabhach etc. It wouldn’t have been [v] as in modern Sc G, but more like Irish in that respect.
Croy in the Central Belt is recorded in that form from 1369. Nearer home, Croy Brae near Culzean is nowadays more often called Electric Brae, it’s where the road looks to be going uphill when it’s actually going down, so cyclists can play at freewheeling uphill! I think these are cruadh.