1911 Encyclopædia Britannica/Dalgarno, George
DALGARNO, GEORGE (c. 1626–1687), English writer, was born at Old Aberdeen about 1626. He appears to have studied at Marischal College; but he finally settled in Oxford, where, according to Wood, “he taught a private grammar-school with good success for about thirty years,” and where he died on the 28th of August 1687. He was master of Elizabeth school, Guernsey, for some ten years, but resigned in 1672. In his work entitled Didascalocophus, or the Deaf and Dumb Man’s Tutor (Oxford, 1680), he explained, for the first time, the hand alphabet for the deaf and dumb, though he does not claim to have invented this method of communication. Twenty years before the publication of his Didascalocophus, Dalgarno had given to the world a very ingenious piece entitled Ars Signorum (1661), dividing ideas into seventeen classes, to be represented by the letters of the Latin alphabet with the addition of two Greek characters. Among the Sloane manuscripts are several tracts by Dalgarno, further elucidating his system of universal shorthand. Leibnitz on various occasions alluded to the Ars signorum in commendatory terms.
The chief works of Dalgarno were reprinted (1834) for the Maitland Club.