Adjustment of Traverses

The procedure used for the adjustment of a traverse should reflect the estimated precision of the methods employed for measurement of angles and lengths. The Least Squares method is best adapted for this purpose. The adjustment of a compass traverse (for which only two condition equations are required) is shown to depend on the quantity R (proportional to the product of the length squared times the ratio of the weight of the length to the weight of the bearing). Large values of R result in large corrections to bearings and, conversely, small values of R yield large corrections to lengths. The Compass Rule (R = 1) and Crandall's Rule (R = 0) are shown to be special cases. The adjustment of transit traverses (for which three condition equations are required) depends on the estimated weights of the individual lengths and angles. Two five sided traverses, each with a perimeter of 3,600 ft and a closure ratio of 1/6000 are used as illustrations.