Charles Mason's Journal from the Transit of Venus journey with Jeremiah Dixon on the H.M.S. Seahorse, January 8, 1761 to April 3,1762. Includes an account of the attack by the French Frigate Le' Grande. This document was "discovered" in 2012 by Jonathan Peacock, who recognized that the document was incorrectly attributed to an "unknown Seaman".
http://hdl.library.upenn.edu/1017/d/medren/2486434

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Cambridge Digital Library "Board of Longitude" documents pertaining to Charles Mason. Includes correspondence from Mason's wife Mary and their sons William and Doctor Issac requesting renumeration from Mason's work on improving Mayer's tables.
http://cudl.lib.cam.ac.uk/search?keyword=charles+mason

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Cambridge Digital Library - Lunar Tables in Longitude and Latitude according to the Newtonian Laws of Gravity by Charles Mason. Includes an interesting note from Mason regarding his disappointment with the renumeration offered by the Board of Longitude.
http://cudl.lib.cam.ac.uk/view/MS-RGO-00004-00086/1

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​Ed Danson’s definitive book “Drawing the Line : How Mason and Dixon Surveyed the Most Famous Border in America” is a must have for those interested in the Mason and Dixon Line.
http://www.amazon.com/Drawing-Line-Surveyed-Famous-America/dp/0471385026 

Robert D. Hutton’s documentation of many stones on the line. Bob’s inventory also includes a link to “Topozone” maps showing the location of the stones.
http://www.masondixon-line.com/ 

Scanned images of the original field notes from the 1901-03 W.C. Hodgkins Re-survey of the line. The David Doyle-National Geodetic Survey Collection of the Mason-Dixon Line Resurvey.
https://speccol.msa.maryland.gov/pages/speccol/index

Wikipedia reference to the Mason and Dixon Line
http://en.wikipedia.org/wiki/Mason%E2%80%93Dixon_Line

Delaware State Boundary Monument Database – contains descriptions and Latitude/Longitude information for the stones on the Delaware & Maryland boundary by selecting "Boundaries" from the "Framework Categories" menu.
https://de-firstmap-delaware.hub.arcgis.com/datasets/delaware::delaware-boundaries/explore?layer=0&location=39.138944%2C-75.387000%2C8.22

Details from the map of the boundary survey between Maryland and Pennsylvania by Charles Mason and Jeremiah Dixon, 1768. SPECIAL COLLECTIONS (Maryland State Archives Map Collection), MSA SC 1427-74-1/2.
https://msa.maryland.gov/msa/speccol/sc2200/sc2221/000017/000013/html/0000.html

Delaware's State Boundaries, By William S. Schenck
http://www.dgs.udel.edu/publications/infoseries/info6.aspx 
 

Surveyors Historical Society

http://www.surveyorshistoricalsociety.com/

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