John Mitchell’s monumental 1755 map of North America has a curious annotation in the North Carolina Piedmont. About 15 miles southwest of present-day Salisbury, one sees “283 M. Survey’d”. So what 283 miles were surveyed?
The horizontal darker green line is the southern boundary of the Granville District and the “283 M. Survey’d” annotation indicates the distance covered by that survey from its origin on the Outer Banks. On the image below, the red X marks the location of that annotation.
So, exactly how accurate was the mid 18th Century survey of the Granville Line?
According to Google maps, the distance is 286.55 miles. One could reasonably argue that the 3+ mile discrepancy is due to poor cursor placement on my part and that the original survey was spot on!