George Dalgarno (c.1616-1687) was born in Aberdeen but spent much of his life teaching at a private grammar school in Oxford. In Didascalocophus, Dalgarno fits the language of the deaf into his general scheme for a theory of signs, what he calls 'sematology'.
Dalgarno's knowledge of & work on 'brachygraphy' - shorthand - brought him into contact with some of the people who later formed the nucleus of the Royal Society, such as Seth Ward, Bishop of Salisbury & John Wallis, who devised a method for teaching deaf people. Dalgarno was buried in the parish of Mary Magdalen, Oxford.
Didascalocophus, or the deaf and dumb man's tutor, to which is added a discourse of the nature and number of double consonants: both which tracts being the first (for what the author knows) that have been published upon either of the subjects, by George Dalgarno, 1680. (Action on Hearing Loss Library).