Door mijn gedaan ; Done by me … Over the course of a century, between 1715-1815, approximately 140 girls from Middelburg were educated by more than twenty teachers. Maria Letellier was the most prolific and likely the most influential teacher, with her name appearing 23 times on samplers from the 1750s to the 1770s. She was followed by teachers Tannetje Wackeroet, whose name appeared 18 times, and Adriana de Vroe, with 15 times her name on a sampler..