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negative if point B is lower than point A.)
When the distance between points A and B is large or if the height distance
is great:
(1) Divide the distance into a number of sections and determine the height
difference of each section.
(2) The height difference between points A and B is the total of the height
differences of all the sections.
The general formula is:
Altitude of the required point = altitude of known point + total of backsight
values - total of foresight values. NOTE: This simple leveling technique has
no error check. It is better to measure from A to B and then measure back to
A so that the error of closure can be calculated.
4.4 Horizontal Circle and Vernier Reading
Your instrument is equipped with an easy to read horizontal circle for simple
angle turning. It is graduated every single degree and is numbered every 10
degrees.
