"These works, you see, are open on the side of the moat, so that if carried they would offer the assailants no shelter from arrows from the walls, while being triangular in shape they would be flanked by our fire. Each of these three forts should have a light drawbridge running across the moat to the foot of the wall, thence a ladder should lead to an entrance to be pierced through the wall, some fifteen feet above the level of the moat; by this means the garrison could, if assailed by an overwhelming force, withdraw into the castle. These outposts would render it--so long as they were held--impossible for storming-parties to cross the moat and place ladders, as they did on the last occasion. The first task will, of course, be to quarry stones. As soon as sufficient are prepared for one of these outworks you should proceed to erect it, as it would render one side at least unassailable and diminish the circuit to be defended. As soon as one is finished, with its drawbridge, ladder, and entrance, proceed with the next. I would build the one at the rear first. As you see from this plan, the two walls are to be twenty feet high and each ten yards long, so that they could be defended by some twenty men. After they are built I would further strengthen them by leading ditches from the moat, six feet deep and ten feet wide, round them. The earth from these ditches should be thrown inside the walls, so as to strengthen these and form a platform for the defenders to stand on. If the earth is insufficient for that purpose the moat can be widened somewhat."