have sent one of their men under the disguise of a fugitive, who gained authority and confidence with the enemy, which he afterward used for his own benefit. Many by this means have learned the procedures of the guards, and through this knowledge have taken the town. Some have blocked the gate so that it could not be locked with a cart or a beam under some pretext, and by this means, made the entry easy to the enemy. Hannibal persuaded one to give him a castle of the Romans, and that he should feign going on a hunt at night, to show his inability to go by day for fear of the enemy, and when he returned with the game, placed his men inside with it, and killing the guard, captured the gate. You also deceive the besieged by drawing them outside the town and distant from it, by feigning flight when they assault you. And many [among whom was Hannibal] have, in addition, allowed their quarters to betaken in order to have the opportunity of placing them in their midst, and take the town from them. They deceive also by feigning departure, as did For minus, the Athenian, who having plundered the country of the Calcidians, afterwards received their ambassadors, and filled their City with promises of safety and good will, who, as men of little caution, were shortly after captured by Forminus.

The besieged ought to look out for men whom they have among them that are suspect, but sometimes they may want to assure themselves of these by reward, as well as by punishment. Marcellus, recognizing that Lucius Bancius Nolanus had turned to favor Hannibal, employed so much humanity and liberality toward him, that, from an enemy, he made him a very good friend. The besieged ought to use more diligence in their guards when the enemy is distant, than when he is near. And they ought to guard those places better which they think can be attacked less; for many towns have been lost when the enemy assaulted them on a side from which they did not believe they would be assaulted.

And this deception occurs for two reasons: either because the place is strong and they believe it is inaccessible, or because the enemy cunningly assaults him on one side with feigned uproars, and on the other silently with the real assaults. And, therefore, the besieged ought to have a great awareness of this, and above all at all times, but especially at night, have good guards at the walls, and place there not only men, but dogs; and keep them ferocious and ready, which by smell, detect the presence of the enemy, and with their baying discover him. And, in addition to dogs, it has been found that geese have also saved a City, as happened to the Romans when the Gauls besieged the Capitol. When Athens was besieged by the Spartans, Alcibiades, in order to see if the guards were awake, arranged that when alight was raised at night, all the guards should rise, and inflicted a penalty on those who did not observe it. Hissicratus, the Athenian, slew a guard who was sleeping, saying he was leaving him as he had found him.

Those who are besieged have had various ways of sending news to their friends, and in order not to send embassies by voice, wrote letters in cipher, and concealed them in various ways. The ciphers are according to the desires of whoever arranges them, the method of concealment is varied. Some have written inside the scabbard of a sword. Others have put these letters inside raw bread, and then baked it, and gave it as food to him who brought it. Others have placed them in the most secret places of the body. Others have put them in the collar of a dog known to him who brings it. Others have written ordinary things in a letter, and then have written with water (invisible ink) between one line and another, which afterwards by wetting or scalding (caused) the letter to appear.

This method has been very astutely observed in our time, where some wanting to point out a thing which was to be kept secret to their friends who lived inside a town, and not wanting to trust it in person, sent communications written in the customary manner, but interlined as I mentioned above, and had them hung at the gates of a Temple; which were then taken and read by those who recognized them from the countersigns they knew. Which is a very cautious method, because whoever brings it can be deceived by you, and you do not run any danger. There are infinite other ways by which anyone by himself likewise can find and read them. But one writes with more facility to the besieged than the besieged do to friends outside, for the latter can not send out such letters except by one who leaves the town under the guise of a fugitive, which is a doubtful and dangerous exploit when the enemy is cautious to a point. But as to those that are sent inside, he who is sent can, under many pretexts, go into the camp that is besieged, and from here await a convenient opportunity to jump into the town.

But let us come to talk of present captures, and I say that, if they occur when you are being fought in your City, which is not arranged with ditches inside, as we pointed out a little while ago, when you do not want the enemy to enter by the breaks in the wall made by artillery [as there is no remedy for the break which it makes], it is necessary for you, while the artillery is battering, to dig a ditch inside the wall that is being hit, at least thirty arm lengths wide, and throw all (the earth) that is excavated toward the town, which makes embankments and the ditch deeper: and you must do this quickly, so that if the wall falls, the ditch will be excavated at least five or six arm lengths deep. While this ditch is being excavated, it is necessary that it be closed on each side by a block house. And if the wall is so strong that it gives you time to dig the ditches and erect the block houses, that part which is battered comes to be stronger than the rest of the City, for such a repair comes to have the form that we gave to inside ditches. But if the wall is weak and does not give you time, then there is need to show virtu, and oppose them with armed forces, and with all your strength.

This method of repair was observed by the Pisans when you went to besiege them, and they were able to do this because they had strong walls which gave them time, and the ground firm and most suitable for erecting ramparts and making repairs. Which, had they not had this benefit, would have been lost. It would always be prudent, therefore, first to prepare yourself, digging the ditches inside your City and throughout all its circuit, as we devised a little while ago; for in this case, as the defenses have been made, the enemy is awaited with leisure and safety. The ancients often occupied towns with tunnels in two ways: either they dug a secret tunnel which came out inside the town, and through which they enter edit, in the way in which the Romans took the City of the Veienti:or, by tunnelling they undermined a wall, and caused it to be ruined. This last method is more effective today, and causes Cities located high up to be weaker, for they can be undermined more easily, and then when that powder which ignites in an instant is placed inside those tunnels, it not only ruins the wall, but the mountains are opened, and the fortresses are entirely disintegrated into several parts.

The remedy for this is to build on a plain, and make the ditch which girds your City so deep, that the enemy can not excavate further below it without finding water, which is the only enemy of these excavations. And even if you find a knoll within the town that you defend, you cannot remedy it otherwise than to dig many deep wells within your walls, which are as outlets to those excavations which the enemy might be able to arrange against it. Another remedy is to make an excavation opposite to where you learn he is excavating: which method readily impedes him, but is very difficult to foresee, when you are besieged by a cautious enemy. Whoever is besieged, above all, ought to take care not to be attacked in times of repose, as after having engaged in battle, after having stood guard, that is, at dawn, the evening between night and day, and, above all, at dinner time, in which times many towns have been captured, and many armies ruined by those inside.

One ought, therefore, to be always on guard with diligence on every side, and in good part well armed. I do not want to miss telling you that what makes defending a City or an encampment difficult, is to have to keep all the forces you have in them disunited; for the enemy being able all together to as sault you at his discretion, you must keep every place guarded on all sides, and thus he assaults you with his entire force, and you defend it with part of yours. The besieged can