On the Edge: Mapping North America’s Coasts by Roger M. McCoy (review)

Though I rarely write book reviews, I readily agreed to evaluate On the Edge because its subtitle, Mapping North America’s Coasts, suggests a concise survey of coastal mapping by Canada, the United States, and perhaps Mexico. I had expected a revealing discussion of depth sounding and overhead imaging, including lidar and satellite remote sensing, but what I found was a history of coastal exploration along the continent’s northern reaches – decent coverage of the search for a Northwest Passage, but very little about coastal cartography after World War I. My initial disappointment was tempered by the serendipitous discovery of a highly readable laic history of the exploration (and mapping) of the polar regions between Greenland and eastern Siberia. What follows is unquestionably a favourable review.

Some publishers think a book’s title is a point-of-sale ad, much like artwork on the cover, and they favour glib catchphrases, however misleading. The main title (On the Edge) suggests an impending economic or psychological collapse and warrants clarification, but the subtitle is much too broad. “Exploring and Mapping the North American Arctic” would have been more accurate, and for me no less enticing.

That said, I applaud Roger McCoy’s insights into how the most forbidding parts of what I call the “first coastline” (Monmonier 2008, 163–64) were inscribed on geographical maps. In temperate and tropical areas, this high-water shoreline can be sketched from a ship cruising along the coast, whereas in the Arctic a vessel might be locked in ice for months, far from a shore approached only on foot or by dog sledge.

McCoy is a professor emeritus of geography at the University of Utah. His publications include numerous articles on remote sensing for petroleum exploration and a book-length history of Alfred Wegener’s ill-fated endeavour as an arctic explorer (McCoy 2006). Perhaps his next book will focus on overhead imaging in the Arctic. I hope so.

Although On the Edge lacks a preface, McCoy’s goals and thesis can be inferred from the apt title of his introductory chapter, “The Urge to Discover New Lands and Make Maps.” The hardships he describes make the work seem more an obsession than an urge. Equally apparent is mapping’s largely secondary role of documenting the discovery of and, by so doing, establishing or reinforcing a distant sovereign’s claim to the “new land.” In later chapters McCoy offers a vivid description of the psychological and physiologic stress on these map-makers, many whom starved or froze to death when their food or their strength ran out.

Reviewers are often advised to avoid a chapter-by-chapter description of content, which would be nearly impossible here because McCoy has sliced and diced his narrative into 25 bite-size chapters. He has also crafted 16 black-and-white maps to describe the progress of mapping and the routes of various explorers and their cartographic impact. Though McCoy’s maps excel in legibility and graphic hierarchy, labels on some of them seem excessively large. My key complaint is the absence of bar scales on the first 11 maps, few of which have a geographic scope large enough to preclude a reliable graphic representation of relative distance. Even so, McCoy’s cartography is a valuable synthesis of explorers’ accomplishments. He also includes a few other illustrations, mostly facsimile drawings in chapter 5, which discusses measurement instruments and techniques.

The back matter reflects an intended lay audience and a reliance on both primary and secondary sources. In addition to an eight-page section with 133 endnotes and a five-page bibliography with 99 references (all but nine of them in books and explorers’ journals), McCoy includes a two-page glossary of 27 nautical terms already familiar to most students of maritime history. Particularly useful to lay readers and cartographic scholars alike...