Li Yu smiled and said, "Uncle, I'm here to get you to make something." As she spoke, she took out the blueprint and handed it to Carpenter Chen. "This is called a catapult. I want to place it at the entrance of the village and the low mountain to deal with those bandits. I'll have to trouble you to help me make it quickly."
"Let me see." Carpenter Chen took the blueprint and looked at it for a while before pointing at it and asking, "Xiaoyu, what are these two things and what is this long one for?"
Li Yu pointed at the blueprint and explained, "The long one is a lever long arm. The small yoke at the top of the long arm is used to carry stones and shoot them out. The short one is called a lever short arm. The large yoke at the top of the short arm is filled with stones to act as a sink."
