The old man glanced at him a few times, then looked at Qi Si and said, "My eldest son has gone to serve his duty, so now it's just me and my youngest son working. Li Ma will tell you that I'm slow at making bricks. How many do you need",Old Second and Fourth Uncle Qi left the brick factory and headed straight for the quarry.,He pulled out another thin slate and showed it to everyone: "There are also these kinds. The foreman at the quarry said that these slates can be used for heating floors."。