Figure 7-32.—Computation of area which includes curve segments.TRAMAN), the tangent length T and the chord bearingand distance C~.The crosshatched areas lying between the chordand arc are called segmental areas. To determine thearea of this parcel, you must (1) determine the arealying within the straight-line and chord (also straight-line) boundaries, (2) determine the segmental areas,(3) subtract the segmental area for Curve 1 from thestraight-line boundary area and (4) add the segmentalarea for Curve 2 to the straight-line boundary area.The method of determining a segmental area wasexplained in the EA3 TRAMAN. The straight-line areamay be determined by the coordinate method, asexplained in this chapter. For figure 7-31, the segmentalarea for Curve 1 works out to be 5,151 square feet; forCurve 2, it is 29,276 square feet.Figure 7-32 shows atypical computation sheet forthe area problem shown in figure 7-31. Included withthe station letter designations in the station column aredesignations (Chord #1 and Chord #2) showing thebearings and distances that constitute the chords ofCurves 1 and 2. The remainder of the upper part of theform shows the process (with which you are nowfamiliar) of determining latitudes and departures fromthe bearings and distances, coordinates from thelatitudes and departures, double areas from crossmultiplication of coordinates, double areas from thedifference between the sums of north and sums of eastcoordinates, and areas from half of the double areas. Asyou can see in figure 7-32, the area within thestraight-line boundaries is 324,757 square feet. Fromthis area, segmental area No. 1 is subtracted. Thensegmental area No. 2 is added.To obtain the area of the parcel as bounded by thearcs of the curves, you must add or subtract thesegmental areas depending on whether the particulararea in question lies inside or outside of the actualcurved boundary. In figure 7-31, you can see that thesegmental area for Curve 1 lies outside and must besubtracted from the straight-line area, while that forCurve 2 lies inside and must be added. With thesegmental areas accounted for, the area comes to348,882 square feet or 8.01 acres.The second method of determining a curved-boundary area makes use of the external areas ratherthan the segmental areas of the curves, as shown infigure 7-33. The straight-line figure is defined by thetangents of the curves, rather than by the chords. Thismethod may be used as an alternative to the chordmethod or to check the result obtained by the chordmethod.The computation sheet shown in figure 7-34followsthe same pattern as the one shown in figure 7-32.However, there are two more straight-line boundaries,7-22

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