Kushinji pondered for a moment and nodded. Long arrows flew easily, increasing friction to fix the trajectory—though he couldn't explain the reasons behind these truths, he still had tangible experience and understanding.
Then, Xiulote discussed an extremely important part of the Han crossbow, the aiming device, Wangshan.
"A vertical strip should be added to the crossbow machine, with the side used to assist aiming and ensure the accuracy of the target. Also, five large divisions should be marked on it, each divided into two half degrees. Thereby determining the aiming orientation and clarifying the specific shooting angle," he explained.
At this point, Kushinji fell into thought. He looked at the diagram drawn by His Highness, found a wooden stick, and marked evenly divided angles on it. Then, he held the stick in front of the crossbow and gestured, finally having a realization.