英语翻译经过系统的非平衡点M作一个在每一点都与该系统的轨线不相切的直线段,即在每一点都与方向不同的直线段.我们称这种线段

Makes one after system's non-balance point M in each spot the tangential path which does not contact with this system's gago line, namely in each spot with direction different tangential path. We said that this kind of line segment to not cut the line segment, records makes L., because selects M right and wrong balance point M, also P (x, y) with Q(x, y) continuously, therefore this kind not cuts the line segment to do comes out