Brittonic languages
This idea is disputed by the "Dictionary of the Scots Language"; and the occurrence in Gospatrick's Writ of the word "wassenas" 'dependants', thought to be from the same word "gwas", is evidence against Jackson's theory. Koch notes that the alternation between "gwa-" and "go-" is common among the Brittonic languages and does not amount to a systematic sound change in any of them.