Example.
With a surveyor compass the angles observed in traversing the lines AB, BC, CD, DE and EF are as. Compute the included angles and indicate them in a neat sketch.
Solution: Given figure shows this traverse. The first back bearings of all lines are calculated and noted in the table shown below:
∠B = 55° 30′ + 63° 30′ = 119° 00′ Ans.
∠C = 63° 30′ + 70° 00′ = 133° 30′ Ans.
∠D = 70° 00′ + 45° 30′ = 115° 30′ Ans.
∠E = 45° 30′ + 72° 15′ = 117° 45′ Ans.