Building a Border: The Material Transit of Scientific Labor

Abstract The U.S.-Mexico Boundary Commission (1849–1855) was a joint effort between the two countries to survey the new border, as designated by the Treaty of Guadalupe Hidalgo (1848) and later the Gadsden Purchase (1854). This article examines the scientific corps of the U.S. Boundary Commission and its dual role in manufacturing a national border and scientific personhood. While studies on exploration and empire generally examine the cartographic output of these state-sponsored missions, this article centers on the embodied practices of surveying. It considers how the technical procedures and practices of surveying produced spaces of scientific knowledge and scientific subjects. When U.S. surveyors traveled to the Indigenous territories of what was formerly northern Mexico in 1849, they began their fieldwork—observing, collecting, and recording the natural phenomena that surrounded them. I argue that as they moved through space, they contoured the nation—creating a field coherent to the state via their scientific work. Their fieldwork was a mobile technology of place-making. Assembling the astronomical and surveying equipment, positioning their bodies with the utmost care to record the motion of stars, igniting flashes of gunpowder to mark time, laboring for hours calculating spherical triangles, and uprooting trees that obstructed sight lines were all acts that constituted both the surveyor and the border. I draw on textbooks, memoirs, congressional reports, and commission records to demonstrate how engineers of the U.S. Boundary Commission crafted themselves as they built a border.