Question: What town is closest to the castle once owned by the Scottish inventor who invented a military cannon described by Isaac Newton as "destructive to the human species"?

 His surname is sometimes spelt as Gregorie, the original Scottish spelling.  He inherited Kinnairdy Castle in 1664. David Gregory (20 December 1625 – 1720) was a Scottish physician and inventor.  Three of his twenty-nine children became mathematics professors.  He is credited with inventing a military cannon that Isaac Newton described as "being destructive to the human species".  Copies and details of the model no longer exist.  Gregory's use of a barometer to predict farming-related weather conditions led him to be accused of witchcraft by Presbyterian ministers from Aberdeen, although he was never convicted. <SEP> Kinnairdy Castle is a tower house, having five storeys and a garret, two miles south of Aberchirder, Aberdeenshire, Scotland.  The alternative name is Old Kinnairdy. <SEP> Jean Claude Jacob was a serf from the Jura Mountains, supposedly 120 years old, who was brought from his native place to figure as "dean of the human race" in Paris at the Festival of the Federation of July 1790.  Thomas Carlyle wrote of Jacob in :Having seen the Human Species itself, to have seen the 'Dean of the Human Species,' ceased now to be a miracle.  Such 'Doyen du Genre Humain, Eldest of Men,' had shewn himself there, in these weeks: Jean Claude Jacob, a born Serf, deputed from his native Jura Mountains to thank the National Assembly for enfranchising them.  On his bleached worn face are ploughed the furrowings of one hundred and twenty years.  He has heard dim patois-talk, of immortal Grand-Monarch victories; of a burnt Palatinate, as he toiled and moiled to make a little speck of this Earth greener; of Cevennes Dragoonings; of Marlborough going to the war.  Four generations have bloomed out, and loved and hated, and rustled off: he was forty-six when Louis Fourteenth died.  The Assembly, as one man, spontaneously rose, and did reverence to the Eldest of the World; old Jean is to take seance among them, honourably, with covered head.  He gazes feebly there, with his old eyes, on that new wonder-scene; dreamlike to him, and uncertain, wavering amid fragments of old memories and dreams.  For Time is all growing unsubstantial, dreamlike; Jean's eyes and mind are weary, and about to close, — and open on a far other wonder-scene, which shall be real.  Patriot Subscription, Royal Pension was got for him, and he returned home glad; but in two months more he left it all, and went on his unknown way. <SEP> The Turing Gateway to Mathematics (TGM) is an Impact Initiative at the University of Cambridge in the UK.  As a knowledge intermediary for the mathematical sciences, it is overseen by the Isaac Newton Institute (INI) at the Centre for Mathematical Sciences (CMS) adjacent to the Isaac Newton Institute.  The Turing Gateway to Mathematics is an intermediary for knowledge exchange for both professional and academic users of mathematics.  Each year the TGM organizes multiple events and workshops that feature expert speakers from various industries, governments and scientific organisations that discuss mathematical technical and models, presented by leaders from diverse backgrounds, such as the health care and finances.