Shibboleths

A passage from a letter by Thomas Andrew Knight, as given by Alexander Walker in Intermarriage: or, The mode in which, and the causes why, beauty, health, and intellect, result from certain unions, and deformity, disease, and insanity, from others: demonstrated by delineations of the structure and forms, and descriptions of the functions and capacities, which each parent, in every pair, bestows on children,- in conformity with certain natural laws, and by an account of corresponding effects in the breeding of animals (1839):

A celebrated French civil engineer, M. Polonceau, visited me some years ago, bringing with him a young French gentleman, who spoke English eloquently, and perfectly like an Englishman, though he had been in England only two years, and, as he assured me, knew nothing of the language previously, nor had ever heard it spoken. I asked him whether he could pronounce the English name Thistlethwaite, and he instantly pronounced it most distinctly and perfectly. The next day, when talking of other matters, he said that he had some Irish relations; and it appeared that his grandmother, on the female side, whom he had never seen, was an Irishwoman. Hence arose, I do not at all doubt, his power of so readily pronouncing the word I had prescribed. A French gentleman at Paris boasted to me that he could pronounce correctly any English word. I proposed Thistlethwaite to him, when, instead of trying, he exclaimed, “Ah, barbare!”