Required to lay down a Map of 20 Perches to an inch, from the following Notes, and find the Area.

TO FIND THE

CONTENT OF LAND,

BY

CALCULATION.

THE foregoing method of dividing a map into Triangles and Trapeziums, although it appears to be demonstrably true in theory, it is not to be depended on in practice, where accuracy is required; for a map may be so divided several ways, and will generally give as many different areas; therefore I shall not enlarge upon it here, but proceed to shew how the true Area may be found, by difference of latitude and departure.

DEFINITIONS.

1. Meridians are North and South lines supposed to pass through every station, parallel to each other.

2. The difference of Latitude, or Northing or Southing of any line, is the distance that one end of the line is North or South from the other-Thus in the following figure

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