The craftsman is responsible for digging the ditch. The head of the hand plough is 5 inches wide, and the two hand ploughs are coupled (ǒu), and one coupling excavates a small ditch 1 foot wide and 1 foot deep. The width and depth of the ditch in the field are doubled by two, and the width is two feet and the depth is two feet. Nine farmers work together on the field of one well, and the ditch between the wells is 4 feet wide and 4 feet deep. The land that is 10 miles square is called cheng, and the land between cheng and cheng, which is 8 feet wide and 8 feet deep, is called 洫 (xù). The land of 100 miles square is called Tong, and the one between Tong and Tong is 2 fathoms wide and 2 feet deep is called Hu, and Hun leads directly to the river. The names of the various ditches are recorded here.

In the topography of the world, there must be a river between the two mountains, and there must be a road on the bank of the big river. Whenever a ditch is dug that violates the veins of the land, it is called a water flow. If the flow of water is not smooth, it is also called the flow of water. The ditch dug flows 30 miles downstream, and the width doubles.

Where the stagnant water is channeled, the channels opened should be straight and staggered along the terrain. In order for the water to become an abyss, the channel must be bent more than at right angles. Whenever a ditch is opened, it must follow the flow of water; Whenever an embankment is built, it must follow the terrain. Those who are good at digging ditches can use the potential of the water to wash away obstacles, and those who are good at building embankments can use the mud accumulated by water to thicken the embankment. Where the construction is made, the width of the lower foundation is equal to the height of the embankment, and the width of the upper base is gradually reduced by one-third compared with the lower foundation.

The large embankment is thickened by the lower base and the outer side is thinned upwards by an increased proportion. When digging a canal and building an embankment, it is necessary to first use the progress of several people as the standard of daily workload, and then calculate the number of days and the number of people required to complete the length of 1 mile, and then calculate the number of manpower used in the whole project. When the plate is tied with rope, the rope ties the plate too tightly, and the result is the same as if the plate was not tied with rope.

The height of the ridge of the thatched roof is one-third of the depth of the front and back of the house, and the height of the ridge of the tiled roof is one-quarter of the depth of the front and back of the house. Round barns, cellars, square barns, and city walls, the thickness of the upper part of their walls is gradually reduced to one-sixth of the height of the wall. The height of the middle of the road in front of the stairs is one-twelfth the width of the two sides. The water channel in the palace is 3 feet deep. The ratio of wall thickness to height is 3 feet thick and 9 feet high.

The car man is responsible for the production of utensils, half of the right angle is called xuan, the angle of one and a half is called 欘 (zhú), the angle of one and a half is called ke, and the angle of one and a half is the curvature of the chime.

The lower part of the shelter is 1 foot 1 inch long, the middle straight section is 3 feet 3 inches long, and the upper end is 2 feet 2 inches long when it bends backwards. From the shelter end, follow the tree to the first end, and use the straight-line distance within the two ends as a string, and the length of the string is exactly equal to the length of one step. Hard land should be turned with straight soil (cì) and soft land should be bent with 庛 curved 耜. The straight wall is conducive to pushing into the soil, and the bent wall is conducive to turning the soil, and the angle of the bending is the same as the chime, which is suitable for all kinds of land.

The driver is responsible for building the wagon. Ke is 3 feet long, 3 inches wide, and 1 and a half inches thick, and divides the length of Ke into 5 equal parts, and uses 1 equal part of the length as the length of the axe blade. The log in the center of the wheels of the cart is 1 foot 5 inches long, and the circumference of the log is 4 feet 5 inches. The straight bar connecting the rim (wǎng) and the hub (gǔ) is 4 feet 5 inches long, 3 inches wide, and 1 inch thick. The circumference of the teeth is 2 zhang 7 feet.

When driving in swamps, the log in the center of the wheel should be shorter; When driving in the mountains, the log in the center of the wheel should be long; The short logs are convenient, and the long logs are stable. When driving in the swamp, the wheel teeth should make the yin side of the wood face outward, and when driving in the mountains, half of the yin and yang sides of the wood should be facing outward; The wheel teeth make the yin side of the wood face outward, it is easy to make the car float and slip without sticking mud, and the wheel teeth make the yin and yang sides of the wood face outward to keep it intact and not be damaged by the rocks.

Divide the height of the wheel into 6 equal parts, and use 1 equal part as the girth of the tooth. The log in the center of the wheel of the cypress wheel is 3 feet long, the circumference of the log is 6 feet, the straight bar connecting the rim and the hub is 3 feet long, the circumference of the teeth is 1 zhang 8 feet, and the height of the wheel is divided into 5 equal parts, and the length of 1 equal part is used as the circumference of the teeth.

The large wheels are 9 feet high, the 绠 (bǐng) left on the side of the teeth is 1 inch wide, and the horizontal logs on both sides of the trunk are 8 feet long. The two sides of the sheep cart are 7 feet long. The cypress cart trunk is lined with 6 feet of horizontal wood. Make two straight logs for driving livestock in front of the ox cart, and the straight wood is three times the height of the wheel. Divide the straight wood into 3 equal parts, 2 equal parts in front and 1 equal part in the back, and chisel the hook of the shaft in this position. The rails are 6 feet wide, and the bentwood resting on the necks of oxen and horses is 6 feet long.

(5) Bow man

The bow man is responsible for making the bow, and the six materials must be taken according to the season. Once all six materials are available, a skilled craftsman will combine them into a bow. the bow is dry, so that the arrow can shoot far; bow horns, for the speed of the arrow; Bow tendons, so that the arrow can be shot deeply; Bow glue, in order to make the bow body tightly combined; Bow wire, in order to make the bow body firm; Bow lacquer, so that the bow body can withstand frost and dew.

The quality standards for dry timber are divided into 7 grades: Zhemu is the first-class, 檍 (yì) wood is second-class, mulberry wood is second-class, orange wood is second-class, papaya is second-class, wattle wood is second-class, and bamboo is the second-class. Whenever you choose dry wood, the color should be red and black and the sound of percussion should be clear; If the color is red and black, the wood will be tough, and the sound will be smooth. When cutting the bow trunk, in order to seek a long shot, it is necessary to use the curvature of the dry wood in reverse; In order to shoot deep, you need to use straight wood. The way to deal with dry timber is to dissect the dry timber without slanting the saw, so that the bow is not twisted.

Where the bow horn is chosen, the horns of the cattle slaughtered in autumn are thick, and the horns of the cattle slaughtered in the spring are thin; The horns of the calf are straight and moist, and the horns of the old cow are not straight and dry; The horns of a cow that have been sick for a long time will be injured and will be uneven, and the thin horns will not be moisturized. The horns should be white in color and thick at the ends. The root of the horn is close to the cow's brain and is moistened by the brain qi, so it is relatively flexible, so it has a natural tendency to bend, and the color is whitish, which is a sign of the tendency to bend.

The middle part of the horn is often attached to the bend of the horn, which makes this section of the horn tough and blue in color, which is a sign of toughness. The end of the horn is far away from the cow's brain, and it cannot be moistened by the brain, so it is more brittle, brittle makes it more flexible, and the end of the horn is thick, which is a sign of flexibility.