I could see that we were nearing the mouth another tunnel. The mountainsides were closing in fast upon us. But the girl was still intent upon opening the window, which had been closed because we had to pass through tunnels. I didn't know why she wanted it open, and felt it was just a silly whim. So I sat still, feeling bitter and watching her cold hands struggling to lift it.
Then with a terrific noise the train rushed into the tunnel, and at the same time the window opened with a crash. Through the window came billows of air black with soot from the train's coal-burning engine The smoke dashed too suddenly against my face for me to protect myself with a handkerchief.