Figure 7-15.—Sample pages from traverse table.in departure. The corrections, however, are opposite insign to the error of closure.distances of from 1 to 100 feet. For a particular traverseline, you determine the latitudes and departures bybreaking down the distance, moving decimal points, andadding up results as in the following example:Traverse Tables/Adjusting Bearingsand DistancesSuppose you want to determine the latitude anddeparture for a traverse line 725.32 feet long, bearingN15°30'E. To get the latitude, do it as follows. In thelatitude column under 15 1/2°, lookup the latitude for70 feet. You read 67.45 feet. If the latitude for 70 feet is67.45 feet, the latitude for 700 feet is 674.50 feet. Notethis in your notes.In computing latitudes and departures, yourarithmetical calculations can be greatly expedited by theuse of a traverse table, in which latitudes anddepartures for any bearing and distance can bedetermined mostly by looking for them in the table.Figure 7-15 shows sample pages from a table thatgives angle-of-bearing values to the nearest quarter-degree (15'). More precise tables give angular values tothe nearest 01'.Next, you look up the latitude for 25 feet under thesame 15 1/2° latitude column, which is 24.09 feet. Thelatitude for 725 feet, then, is 674.50+ 24.09= 698.59feet.Under each of the bearing values at the head of thepage, a double column gives latitudes and departures for7-12
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