For earth walls and rustic construction
Swallows have taught us this craft by building their nests out of mud mingled with wisps and bits of hay or straw to make it bond. Therefore, in places where stones and bricks are lacking, one can use earth to make walls thin and thick. The best for this is light earth, which does not form clumps when plowed, or better, that which in some way mingled with arene, because it can be most easily beaten and tamped down. It is true that it needs to be dampened and cut into clumps with a ditch—spade, and put and placed in this form. This one lasts more and does not require that much effort, and dryness doesn’t make it split or crack. However, since such kinds of earth are not found everywhere, those who live on good and fertile land, after drawing the width and length of their foundations with a rope, drive in long poles and rafters along the edges on each side to support boards between which they throw the earth, making each layer about one foot thick, interspersed with S.S.S—shaped branches of heather or similar things, then they tamp it down and beat it with beaters of three different forms. One is called the mall, which has a triangular form like A, and this is used firstly to tamp down the earth. Then one uses another made of pointed woodblocks fitted onto a thick stick, and this one is used to properly press the earth at the wall’s ends and edges where they adhere to the boards, and is called . The other one is called the bat and is used to flatten and beat the earth for the last time, as shown in C. Then one makes another layer of earth and heather and beats as has been said, and continues thus until completing the wall, which is covered with heather and then with earth. Some intersperse the said wall with rows of bricks. They also make walls with a sloped foot, adding width to the foundations according to how high they want to build the wall. When it is old it whitens, showing that it has saltpeter in it. Which is why, when they fall down, gunpowder makers profit from them.