How do you adjust the optical plummet of a Leica tribrach?

To adjust the optical plummet of a Leica tribrach, first, ensure that the tribrach is securely mounted on a stable surface. Use the leveling screws to center the optical plummet over the survey point by looking through the optical plummet scope and adjusting until the crosshairs align with the point. If necessary, repeat the process until the alignment is accurate. Finally, double-check the leveling of the tribrach to ensure precise measurements.