Technological Models as Object Lessons of Agitation: Multiscale Materiality and Agency of Sand Filtration in an Industrial City, 1895.

How might forces and interactions at the surface of sand particles contribute to material agency with tangible impact on human life? This article explores the multiscale materiality of a technological model and how it catalyzed social action and influenced the development of larger-scale municipal infrastructure systems. It focuses on a demonstration sand filter constructed through civic engagement in Pittsburgh in 1895. This locally embedded community technology, situated in international networks of scientific knowledge, served as a practical "object lesson" in abstract principles of sanitation engineering-publicly demonstrating and validating the counterintuitive ability of local sand and gravel to purify city water. By bridging materials science and engineering with histories of technology, this study contributes to discourses on new materialism by identifying nonhuman agency at the nano- and micrometer scale and tracing its implications for public health, civic identity, and infrastructure design.