James Boswell's uncle John was a member of a sect known as the Glasites.
Maria Jacoba Cornelia van EfferenBorn ca. 1719
Countess van Efferen. Married to Hendrik van Utenhove (1715-1767), Heer van Amelisweerd.1 Married (1771) to Maximilien Henri De Saint-Simon (1720-1799), Marquis of Sandricourt
Life with Boswell:
Boswell met Madame Amelisweerd at the assemblies and other social events during his stay at Utrecht in 1763-64. On December 8, he wrote having being told by the Countess of Nassau Beverweerd that "[Madame Amelisweerd] was married at seventen, when one does not know the consequences; said marriage was unequal" and that "Monsieur d'Amelisweerd [was] a rough squire, but jealous of his lady, a charming little woman".
Note 1: The correct spelling seems to be Utenhove without an 'n' at the end. Heer van Amelisweerd was the son of Reinier van Utenhove and Henriette Jeanne de Cabilliau.