80
With the stadia hair of the instrument and the graduation on the staff, you can
measure the distance easily. The stadia interval on the staff multiplies 100 is the
distance. The stadia interval is the interval between the upper hair and the lower hair
on the reticle.
(1) Set up the staff on the target point.
(2) Set up and level the instrument. Sight the telescope to the staff. Record the stadia
interval between upper hair and lower wire as “1”.
(3) The distance “L” between instrument and staff is L=100x1.
