Question

measurement of horizontal angles theodolite by method of repetition

Answer 1

hey mate here we go
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Set up the theodolite at station point O and level it accurately. (The face of the instrument should be left.)Set the vernier A, to zero or 360° by using the upper clamp and its tangent screw. Then loosen the lower clamp direct the telescope to the left hand object A, and bisect A, exactly by using the lower clamp and its tangent screw.Check the reading of the vernier A, and see whether it still reads zero, and then read the other vernier B.Loosen the upper clamp, turn the telescope clock wise and bisect the right hand object (B) exactly by using the upper clamp and its tangent screw.Read both verniers. The object of reading the verniers is to obtain the approximate value of the angle. (Suppose the mean reading is 50°4).Loosen the lower clamp and turn the telescope clock wise until the object (A) is sighted again. Bisect A, accurately using the lower tangent screw. Check the vernier readings which must be same as before.Loosen the upper clamp, turn the telescope clockwise and again sight towards B. Bisect B, accurately by using the upper tangent screw.
hope it helps