Travel any highway or medium-sized road across the border between Maryland and Pennsylvania, and you’re likely to see a sign denoting the Mason-Dixon Line. The line is popularly known as the demarcation between the North and the South, but it has a far richer history, detailed by Sally M. Walker in her new book, Boundaries: How the Mason-Dixon Line Settled a Family Feud and Divided a Nation.
The line was originally born from a boundary dispute between the colonies of Maryland and Virginia. The charters given to both George Calvert in Maryland and William Penn in Pennsylvania by the British monarch cited the fortieth parallel of latitude as the dividing line between the colonies, but there was no physical marking on the land, and only a vague understanding of where the fortieth parallel actually lay. The result was a series of border disputes, with both colonies claiming some land and demanding taxes from those residing on it. Complicating the problem was the boundary of the three lower counties of Pennsylvania–now the state of Delaware–whose boundary line had proven extremely difficult to survey.
Into this dispute stepped Charles Mason and Jeremiah Dixon, an astronomer and a surveyor, respectively, who had made a name for themselves in England. They were hired by the leaders of the two colonies to properly survey and mark the boundary. In a journey that took them to the very edge of land settled by Europeans, they created the famous line that bears their name. In the years after their feat, the line took on additional meaning as the boundary between the North and South, and between slaveholding states and free states.
In explaining the need for the line, Walker gives a great deal of historical background on the colonies and the men who founded them, and on the border disputes and hardships that colonists faced. She also touches on the significance the line took on after it was created. Boundaries takes a subject that many people, including those who live in close proximity to the Mason-Dixon Line, know little about and makes it a compelling story.
Boundaries is part history book, part primer on surveying. Walker does a good job of explaining complicated mathematical and astronomical concepts in describing the process of surveying using the stars, but those sections could be a bit intimidating to kids who don’t have a strong mathematical foundation. The book can be enjoyed even without grasping all of the details of surveying, but kids with an interest in math and the stars will find those sections fascinating.
Review by Kate Sweeney
Boundaries: How the Mason-Dixon Line Settled a Family Feud and Divided a Nation by Sally M. Walker; Candlewick; c2014