This essay provides a close reading of Capital, Volume I, Chapter 15: “Machinery and Large-Scale Industry.” Part one examines Marx’s theory of the capitalist machine. Under capitalist conditions of production, the machine appropriates the worker’s skill, transforming that worker into an interchangeable adjunct or appendage. At the same time, machine driven industry employs women and children in ever-greater numbers, displacing male hands, and feminizing production. Finally, the machine emasculates the workingman and turns the world upside down. To dramatize this emasculation, Marx uses health and safety reports that rely upon gendered anxieties and masculine fears of the social disorder brought about by liberated women. Thus, I argue, Marx utilizes the gendered anxieties of his audience in order to construct an argument against capitalism. The second part of the paper examines the “invisible threads” that bind factory production to domestic, sweated labor. Marx provides an analysis of sweated labor that connects severe forms of economic exploitation to gender ideology, and he takes great pains to render visible the otherwise concealed labor of women in sweatshops. In telling the story of sweatshops, Marx once again finds women’s labor to be a fundamentally important force in capitalist development. Sweating allows some capitalists to accumulate excess profits through artificially cheapened labor. This early accumulation puts those firms in a position to succeed once factory legislation forces them to centralize production and eliminate their “outworkers.” Thus, for Marx, women workers are central to the story of capitalists’ accumulation and capitalism’s development. Yet, at the same, Capital offers a normative vision of labor that assumes the masculinity of the working population and represses the political agency of women workers. The paper ends by comparing Marx’s fundamental ambivalence toward women workers with the more straight-forward “radical paternalism” and gender essentialism of Marx’s contemporary, the U.S. labor leader, William Sylvis. While this comparison highlights Marx’s difference with gender essentialists, nonetheless Marx’s fundamental ambivalence toward the necessity of women industrial laborers leads him to a theoretical blindness regarding the possible militancy of women workers. Even as he rendered visible women’s work in the formal economy, he was unable to see their militancy as workers.