Lewis Hine's 1920 Power house mechanic working on steam pump, one of his "work portraits", shows a working class American in an industrial setting. The carefully posed subject, a young man with wrench in hand, is hunched over, surrounded by the machinery that defines his job. But while constrained by the machinery (almost a metal womb), the man is straining against it--muscles taut, with a determined look--in an iconic representation of masculinity. Photograph By Lewis W. Hine.