Symbolism, Imagery, Allegory
Now it's Marco's turn for a symbolic act of male dominance. At the end of Act I he challenges Eddie to lift a chair by one its legs with only one of his arms. Eddie can't do it. Marco easily hoists it over his head. Eddie basically gets a symbolic beat down. He's emasculated. We haven't seen this kind of behavior from Marco before now. What could've inspired it? Our best guess is that it's Marco's way of responding to the growing tension in the Eddie/Catherine/Rodolpho love triangle.
Eddie has just punked Marco's little brother, by beating him in a supposedly friendly boxing match. The bout ends with Eddie punching Rodolpho a lot harder than the "friendly" bout would seem to require. Eddie's gesture isn't lost on Catherine who immediately invites Rodolpho to dance to "Paper Doll." (See the section above.) Talk about tension.
Marco seems to understand the increasingly intense social situation pretty well. He senses Eddie is about to explode and thus we have the emasculating chair lifting contest. In the stage directions tell us that Marco raises the chair "like a weapon over Eddie's head" (1.691). Is the lifting of the chair Marco's symbolic warning to Eddie? Is it a promise of violence, which Marco later fulfills?