The Marine Sextant, Continued
How a Sextant
A reflected object from the index mirror can be brought into line with
an object viewed directly by moving the index arm along the arc scale
until the reflected object can be seen in the horizon glass. The angle
measurement is read off the arc scale, micrometer drum, and vernier
scale. Figure 8-13 shows how a sextant works.
Figure 8-13. How a sextant works.