Recto: The Houses of the Barbarians (Vitruvius, Book 2, Chapter 1, nos. 3, 4); Verso: The Aeropagus in Athens with Cave Houses (Vitruvius, Book 2, Chapter 1, no. 5).

1530–45

Pen and dark brown ink

19.1 × 14.1 cm (7.5 × 5.6 in)