023r - - - - - A mortar is made so that it weighs three quintals and carries a cannonball flat on the side from which it must exit and round on the side of the cannon, as if it was a cannonball cut in half. It is two pans long. It has to be loaded with xxv lb of powder because it has to be full to the opening and has to fire. Its bottom is not thicker than the opening and is made of one single piece. Its material has to be better than other artillery pieces, and for 4 quintals of fine copper there must only be one quintal of metal so that it absorbs the shock, and so that, when fired with more force, it is more efficient. It has to be used against a door with a large iron cross before the bullet, and once loaded, needs to be covered with a firmly sewed rough canvas which should be completely smeared with turpentine. Four handles need to be added to it while it is cast, it is thus easier to place. The iron cross is fixed to the opening with the canvas covering it. The handles have to be held at its opening’s edge, as you can see. To place it, you need three or four iron pegs of one pan long and as thick as a finger, which have their point like a gimlet, and their body like a screw as they are strongly pulled, and a ring on the other side to turn them with a short stick that fits into the ring. And the pegs are fixed on the door, not straight, because they would not have any strength, but crooked as if you wanted to fix them towards the middle of the mortar, and to do the holes of the handles need to be quite large. In that way, the shooting mortar pushes the pegs back and forth into the door, and makes more damage. Once in place, you need to have saucisse de buckram @ made in this manner: take eight or nine canes of buckram selvage or more if the gap is larger, which have to be as large as four or five fingers, have it sewn in such a way so that it is like an intestine where a stick as thick as a finger can fit. Fill it completely with good
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This one is to be put below an undermined tower with its opening towards the top. One casts two large iron rings and, with a stick or two, four men carry it. They are also used for placing within wall breaches but just half a charge is necessary, that is x lb, and fill the rest with some pebbles and cart stones . Figure at left middle margin
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It needs to be covered entirely with a waxed canvas and rubbed with turpentine and other combustible things. This cover is made to ensure that the bullet does not fall and so that, when the cover is given fire, the powder does not fail. Upon the fuse, you will need to put a good quantity of powder. Some put on the ball a cross of iron which is longer than the mouth of the mortar by two pans. Others only put the ball.
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