Reviewed by: Evolution of the Texas-Louisiana Boundary: In Search of the Elusive Corner by Jim Tiller and John P. Evans Michael Kimaid Evolution of the Texas-Louisiana Boundary: In Search of the Elusive Corner. By Jim Tiller and John P. Evans Jr. (Dallas: William P. Clements Center for Southwest Studies, Southern Methodist University, 2017. Pp. xviii, 455. $60.00, ISBN 978-1-929531-17-2.) Every line on a map tells a story; some are more interesting than others. While most historians might look south when evaluating which story to tell about the lines on the map that frame the state of Texas, Jim Tiller and John P. Evans Jr. look east, to the Texas-Louisiana border, instead. Incorporating a geographical perspective into a historical narrative frame, the result is every bit as interesting as the often-retold story of Texas's southern border and gives fresh insight into the political, economic, and social conditions that produced the line in question and others like it. Tiller and Evans focus on how the early, vaguely defined borderlands separating Texas and Louisiana became over time a sharply defined borderline, a process that hinged on establishing the intersection of the thirty-second parallel and the Sabine River. Early on, the authors identify "both environmental and human factors" that prevented surveyors from determining this point with any accuracy (p. xv). Beginning with the 1763 Treaty of Fontainebleau and the subsequent transfers between Spain, France, and the United States, culminating with the 1803 Louisiana Purchase, early documents were inaccurate and vague with regard to where the meandering river intersected with a fixed coordinate point. As a result, the precise point on which the boundary between Texas and Louisiana hinged was not identified with any accuracy until 1841. The processes that established the initial border were largely political. Early-nineteenth-century expeditions were followed by land surveyors, whose observations contributed to the Public Land Survey System in an attempt to systematize the variables of terrain into a uniform grid. From there, the Joint Boundary Commission of the Republic of Texas and the United States governments largely clarified the boundary, though a remaining gap in the boundary was closed in 1848 by an act of Congress. Nearly one hundred years later, new technologies were applied to make the boundary more precise and accurate and established the line with a precision that remains to this day. While the historical nature of this story is itself very interesting, it is Tiller and Evans's use of geography that makes this volume particularly authoritative and impressive. Here, their archival work stands out as rigorous and thorough. The detail with which they recount surveyors' notes, correspondence, maps, discrepancies, debates, and errors is comprehensive. Historical maps, aerial and landscape photography, geographical information systems analysis, and field notes come together in this volume in groundbreaking and original ways, which demonstrate with clarity the specifics the authors reference in the text. In sum, Jim Tiller and John P. Evans Jr. have done a remarkable job combining archival research and fieldwork to produce this beautiful volume. Like the intersection on the map they have sought to tell the story of, they combine history, geography, and archaeology to tell a story that is exponentially more interesting than one would imagine at first glance, given the history of Texas's more historically resonant southern border with Mexico. Like so many maps of the world, the Texas-Louisiana line was drawn in over the course of [End Page 978] nearly two hundred years. The story is equal parts science and art, objective and subjective, observation and speculation—forces that continue to shape our reality to this day. Michael Kimaid Bowling Green State University Copyright © 2018 The Southern Historical Association