David Taylor's photographic examination of the contentious territory that is the U.S./Mexico border is organized around a series of approximately 260 obelisks that demarcate this boundary, and which were installed in the late 1880s. In the course of pursuing this project, Taylor earned a remarkable degree of access to U.S. Border Patrol, the agents of which often refer to their job in the field as "line work"--a term that is also an apt description...