Illustration for 'The Labours of Mars' by Allain Manesson Mallet

A group of men are busy setting out the outlines of a fortress, fort or fortification (pentagon). Below, a ground plan for a fortress, fort or fortification (square) and two profiles. Below that again, a view of a city. In the upper right corner the number 4 (= the number of the page in the book opposite which the illustration is placed).