Allan Alexander Carswell (born 1935 in Ontario, Canada) became an apprentice at the Canadian Bank Note Company in 1954. He started out studying letter engraving but three years later moved on to picture engraving. At this time, the stamp engraver Yves Baril would become his tutor.
In 1962, Carswell's first stamp engraving was issued: it comprised the portrait of Lord Selkirk on a stamp marking the 150th anniversary of the Red River Settlement. In the following couple of years, Carswell would engrave a good number more Canadian stamps, ending his philatelic output in 1967 with no less than contributions to five issues, among which the high values of the new definitive set.
Carswell would later move on to the Security Bank Note Company in Philadelphia.
You will find Allan Alexander Carswell's database HERE.