Si priores libri responderunt titulis suis et lectorem hucusque cum attentione perduxerunt, edam nunc circa oppugnationes urbium defensionesque στρατηγήματα. Nec morabor ulla praelocutione, prius traditurus quae oppugnandis urbibus usui sunt, tum quae obsessos instruere possint. Depositis autem operibus et machinamentis, quorum expleta iam pridem inventione nullam video ultra artium materiam, has circa expugnationem species στρατηγημάτων fecimus:
I. De repentino impetu.
II. De fallendis his qui obsidebuntur.
III. De eliciendis ad proditionem.
IIII. Per quae hostes ad inopiam redigantur.
V. Quemadmodum persuadeatur obsidionem permansuram.
VI. De districtione praesidiorum hostilium.
VII. De fluminum derivatione et vitiatione aquarum.
VIII. De iniciendo obsessis pavore.
VIIII. De inruptione ex diversa parte quam exspectabimur.
X. De insidiis, per quas eliciantur obsessi.
XI. De simulatione regressus.
If the preceding books have corresponded to their titles, and I have held the attention of the reader up to this point, I will now treat of ruses that deal with the siege and defence of towns. Waiving any preface, I will first submit those which are useful in the siege of cities, then those which offer suggestions to the besieged. Laying aside also all considerations of works and engines of war, the invention of which has long since reached its limit,1 and for the improvement of which I see no further hope in the applied arts, I shall recognize the following types of stratagems connected with siege operations:
I. On surprise attacks.
II. On deceiving the besieged.
III. On inducing treachery.
IV. By what means the enemy may be reduced to want.
V. How to persuade the enemy that the siege will be maintained.
VI. On distracting the attention of a hostile garrison.
VII. On diverting streams and contaminating waters.
VIII. On terrorizing the besieged.
IX. On attacks from an unexpected quarter.
X. On setting traps to draw out the besieged.
XI. On pretended retirements.