Making and Knowing
A minimal edition of BnF Ms Fr 640 in English Translation

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Mortars

Figure Figure

Mortars are made of the best alloy of “métal” and the finest possible rosette so that they do not burst, that is to say one part “métal” and two [parts] fine rosette or old caudron, which is even better. Some of them are of fifteen or seventeen lb. and are loaded with two and a half lb. of grain powder, and they are put on common windows and doors. Others are of a weight of 25 to 27 lb. and are loaded with eight lb. of powder. And in such a way, they are made according to the stress they have to resist. On the outside, they are all the same shape, but in the inside, they are made like a crucible

Figure Figure

narrower on the inside of the bottom and getting wider towards the mouth. And this is to reinforce the bottom, given the quantity of powder they hold, and so that they do not burst. Those of 4 s. lb. are eight lines thick at the bottom, and get thinner in the inside towards the opening, which is of 4 lines. They have xiii “poulsses” long and seven in diameter at the mouth and opening.

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The ones weighing about 27 lb. are ix “pousses” long and the mouth is 6 [pousses] in diameter. At their bottom, they are 6 “lignes” thick, and 3for the mouth. The ones weighing 17 lb are 8 “poulsses” long and the mouth is five. They are all covered together, all the forks, rods, and tools which one uses, with a big canvas or big cloth so that they do not make any noise. It is good that they sit loaded for a while. After the powder has been put in, it is grinded very hard and then tightly pressed paper is put in, then a cake of well pressed wax and, on the wax, another slab of cork that fits in very snugly and that you have to force in. In this way, the powder remains well packed and gives much greater force, and if you wish, you can put on the cork slab one of wood pierced in the middle, if the mortar has a pierced bottom, which is believed to be the easiest and which makes a greater hole because it cannot recoil. And for these that have a pierced bottom, one must have a good gimlet to first make the hole so that the rod, which is made by the point of the gimlet, has before and without noise attached the mortar. And for these, one must cover the button, which is quite sharply filed, with waxed canvas, or add wax to it so that it completely plugs the hole in the bottom. But because the doors are sometimes iron and the iron rods cannot pierce it, an iron fork made like pincers and another iron stick made with three claws, like you see painted, are use. And in this way, the mortar stays in place well and is immediately steadied. The iron rods must come out of the mortar from every point made by the gimlet, namely by three or 4 finger lengths, which all enter in the door. When the mortars are placed, the touch—hole is filled with good powder and inserted in it is a feather shaft filled with tightly pressed powder and moistened with vinegar, or if needed, the powder is firmly pressed with the palms of the hands and, having wet it with some saliva, you shape it like a cocoon or

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Figure at left top margin of folio 168r Figure

rod that we put into the touch—hole, and then, with a rope wrapped around the end of a baston, we ignite it and promptly retreat to take cover. The small mortars of 16 or 17 lb. are attached promptly with a short, hooked rod made like a wimble, and if it is of a good alloy, we can ignite it by hand. It is done in this way for mortars of 27 lb., but then we only put three lb. of powder. The door really needs to be strong so as not to be blown off for seventeenth lb. mortars. Some people use little bells worn by oxen or mules as an door for the mortars. Others load two canons of guns and, with a gimlet and a string, tie them with the opening against the door. If the mortars are good and do not explode, they only recoil and cannot harm if one is next to them.

  • A is a small rod, hooked like the hinge of a door and made as a biron on one end in order to quickly attach a small mortar with handles of fifteen or xvii lb. for a common door or window.

  • B is a small mortar with handles.

  • C is a common mortar of 27 or 30 lb. pierced at the bottom, where a large iron rod passes, button—like on one end made like a biron on the tip so as to quickly hang the mortar against a door that will not be covered with iron plates.

  • D These are slabs of wax, cork and wood for loading the mortar and well packing the powder.

  • E iron fork made in the form of pincers as tall as a man, used to quickly set the mortar without a rod. It must be of soft iron so that the sides fold easily, if needed, and to accommodate the height or width of the door.

  • F is another iron fork of the same height that supports the fork made as pincers and also sustains the mortar, and with its low claw prevents the pincers from recoiling.

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  • G mortar with handles placed with its rod.

  • H knife—like saws to cut, if needed, a portcullis.

  • J the big iron rods that cross and tie the mortar.

  • K are like iron rods, all round and covered with cloths, like all the rest, so as to make the big iron rods, pierced close to the button, turn.

  • L axes that one must always carry to chop and to break, in the fortuitous case that the mortar has left anything entirely.

  • M a large wood mallet for knocking down what was begun and weakened by the axes and “birons”.

  • N are big wheelwright augers and birons for easily cutting a door or window by making large holes close to one another.

  • O crutches as tall as a man that must be carried to put under a portcullis immediately after the canon has been shot and to prevent the portcullis from falling.

  • P are small iron pincers for putting any low mortar against the bolt of a door.