Development of the Short Vowels. The development of the short vowels from Northumbrian Old English to later Cumbrian is perhaps even less eventful than it is in RP English, and will not take up much space. The exact qualities of the short vowels of Old English are inaccessible, but we can certainly get within a couple of IPA characters. In any case, none have changed dramatically in Cumbrian. Northumbrian Old English had an inventory of short vowels something like this:
iy eø
u o
æ
ɑ
By the middle English period, /ø/ had unrounded and merged with /e/, and /y/ had unrounded and merged with /i/. Short /æ/ and /ɑ/ had merged together. I will write this phoneme as /ɐ/ from that point onwards because that is how I represent it in later Cumbrian, and it is perfectly possible that this was the phonetic quality in north-western Middle English as well. By about 1400, then, we have something like this:
i e
u o ɐ
Structurally, this is extremely similar to the later Cumbrian short vowel inventory. Given that we do not know whether short vowels in Old English had exactly the same qualities as their long vowels, and we do know that later Cumbrian did/does not, we could alternatively reconstruct the short vowels of northern Middle English like this: 47
