Draining the basin of Mexico: Science, technology and society, 1608--1808

The colonial project for the desiccation of the basin of Mexico, known as the Desague de Huehuetoca, included river diversions, vast open trenches and a long, deep tunnel. It was designed exclusively to protect elite property in the emerging Spanish viceregal capital of Mexico from floods. Combining flood control with irrigation or water transportation was not originally considered for the design. In this, the Desague differs from earlier and contemporary Italian hydraulic works, which were prompted by the drive of competing polities to assure agricultural production, cohese their hinterlands and consolidate trade networks. Later, individuals did express a desire for change or more productive uses of the project, but by then the early technological and organizational decisions proved to be impossible to undo.; The dissertation focuses on the technological actors involved in the Desague---friars, guild architects, military engineers, and criollo savants---to explain how this conservatism dampened technological and scientific development. Four chapters study each group's social and intellectual background, the material work concluded under their supervision and the ways that they conceptualized the project, including both implemented and discarded proposals, in the context of writings in geometry, architecture and hydromechanics of the era. By combining socio-economic imperatives with the work of technological practitioners in the Desague, the dissertation ascertains why---given New Spain's advantageous endowment with a gigantic natural laboratory in the complex hydrology of the basin and with scientifically-inclined intellectuals---it was not this colony but rather Italy and France that developed scientific hydromechanics, navigable canals, and economically integrated water management.; As an urban-centered project, the Desague conflicted with Indian villages and Spanish rural producers over usage of land, water and labor. Authorities created mechanisms that shifted the costs of the project onto these rural producers, and the drive to perpetuate these arrangements further undermined the development of innovative technologies and a scientific understanding of water. The dissertation provides specific explanations for the relative backwardness of Spanish American scientific and technological development, as seen through the lens of the Desague and the science of water.