A decorative woodcut headpiece features symmetrical floral scrolls and foliage. Two female figures are seated on either side, and a central face or mask is nestled among leaves in the middle.

TO THE MOST POWERFUL

LORDS THE STATES GENERAL

OF THE UNITED PROVINCES.

IT IS well known, Most Powerful Lords, that maritime cities—and those situated on the banks of great navigable rivers—are weak at both ends. This is due to the presence of dry moats or embankments dodanes: sloping earthworks, likely referring here to the "donkey-back" shapes of exposed riverbeds or banks, near which one can approach on dry land, especially when the water is low, right up to the walls or ramparts. But seeing as one can conveniently fortify such weak places through the new invention of sluices original: "Escluses"; these are water-control gates or locks used here as a dual-purpose tool for defense and maritime safety recently come into use, and that furthermore, the moats can serve as deep harbors where ships can be secured and wintered when ice is floating—aiming not only at the improvement of the cities and the country in general, but also at the preservation of the lives and property of seafaring men—it seemed useful to me to provide this description.

It is indeed true that some have urged me to disclose the general subject of fortification while waiting for a more complete description, but it seemed good to me to extract this specific part first. This is so that, by not being placed among many other matters that are not of interest to everyone, it might be better read by many—and especially by those whose judgment can bring about the desired result: