Ontledingen en ontdekkingen van de onsigtbare verborgentheden; vervat in verscheyde brieven,
A 1685 Dutch letter collection by Antoni van Leeuwenhoek, published in Leiden by C. Boutesteyn, describing his microscopic discoveries in letters. The pictures are four decorative woodcut initial letters, N, I, I and M, set in dense scrolling foliage that a designer could borrow for ornamental capitals and borders.
