When the legless man comes through the subway car, clomping that tin cup before him to draw forward and signal the solemn fact of his existence. When he clambers through that silver divide to be born in our midst. When he is there. I know he approaches, soon to pass me by; my heart tightens up as though in tune with his odd Doppler effect. I can't breathe when he draws even. There he is. There he goes.