Model for Descriptive Geometry by A. Jullien - Rotation of a Point about a Vertical or Horizontal Line

Jullien, A. · ca 1880

Figure 1 shows the rotation and projections of point (m, m’) about a horizontal line perpendicular to the vertical plane through point a’. Figure 2 shows the rotation and projections of point (m, m’) about the vertical line perpendicular to the horizontal at point a.