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We then multiply them by the distance 10.40 and the products 8.867456 and 5.43400 are the latitudes and departures of the course; which we enter in the table, omitting the decimals after the fourth place. We find, in a similar manner, the latitudes and departures of the other courses; after which the work is balanced and wrought, as with the Traverse Table.

EXAMPLES.

1. It is required to determine the contents and plot of a piece of land, of which the following are the field-notes-viz.:

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NOTE. When the bearing is due East or due West, the error

in latitude is nothing, and the corrections for latitude must

be distributed among the other courses. So, when the bearing is due North or due South, the error in departure is nothing, and the error in departure must be distributed among the other courses. In the examples for practice, we have not been as careful to have as close balances as must be had, in actual work on the field.

2. Required the contents and plot of a piece of land, of which the following are the field-notes.

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3. Required the contents and plot of a piece of land, from

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4. Required the contents and plot of a piece of land, from

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5. Required the area of a survey, of which the following are the field-notes.

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If, in this example, we assume 1 as the principal station, the double meridian distances will all be plus, and the positive area will exceed the negative.

In balancing, we shall find the error in southing to be .28 ch., and in westing .22 ch. The area is 13 A. O R. 11 P. It should, however, be remarked, that in all the examples the answers may be slightly varied by distributing the corrections.

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In this survey 4 is the most easterly and 9 the most westerly station. The area is equal to 110 A. 2 R. 23 P. It may vary a little, on account of the way in which the balancing is done.

7. What is the area of a survey of which the following are the notes? Make the plot.

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I. To determine the bearing and distance from one point to another, when they are so situated that one cannot be seen from the other.

101. Let A and C be the two points, and AB a meridian passing through one of them. From either of them, as A, measure a course A2, of a convenient length in the direction toward C, and take the bearing with the compass. At 2, take the bearing of a second course, and measure the distance to 3. At 3, take a third bearing and measure to 4. At 4, take the bearing to C, and measure the distance from 4 to C.

3

B

Then, the difference between the sum of the northings and

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