SAILING TO PHILADELPHIA SOURCES

Thomas Pynchon "Mason Dixon"

This is a historical novel about the famous surveyors Charles Mason and Jeremiah Dixon -- mappers of the border between Pennsylvania and Maryland that also made up part of the dividing line between slave states and free states before the Civil War, and globetrotters on a variety of scientific adventures in the later 1700s.

The tale opens with Mason and Dixon meeting in about 1760 to embark, at the behest of the British Royal Society, on a journey to the Southern Hemisphere to observe the Transit of Venus -- the passage of that planet across the sun. Just as they set sail from England, however, they are attacked by a French frigate and several of the crew members are killed.

In accepting a commission to survey the border between Pennsylvania and Maryland, Mason, the expedition's leader, retreats from the hard science of the Transit of Venus.

Mason and Dixon complete their line in 1767, and spend much of the following year surveying a degree of latitude also contracted to them by the Royal Society. 

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