"Leslie appears to have been weak as a child, so much so that he was unable to continue attendance at Leven school, where he was sent after a beginning with his schooling at a small class conducted by a woman in Largo. An elder brother, tutoring him at home, however, discovered his amazing aptitude for mathematics; so his parents sent John to St Andrews University, where his brilliance carried all before it".
It was near the end of his life, on 27 June 1832, that John Leslie was knighted (see notice below from 20 June Morning Post).
"The fame of Professor Leslie has extended over all Europe; he was one of the most acute and brilliant of all the men of science who have rendered Great Britain illustrious in modern times, and formed one of that galaxy of great men - the Playfairs, Broughams, Jeffreys and Horners - who have conferred such lustre upon our Scottish metropolis."
Meanwhile, the Morning Advertiser of 13 Nov emphasised that his rise was not due to the "patronage of any powerful individual or party, or to any adventitious circumstances, but solely to his own talents and industry". John Leslie did not marry and had no children. However, his brother Alexander - an architect-builder in Largo - had a son named James who was a civil engineer of note, as was James's son Alexander Leslie (John Leslie's great nephew). More on them at a future date.