Jevons saw the kettle boil and cried out with the delighted voice of a child;Marshal too had seen the kettle boil and sat down silently to build an engine.

• 杰文斯看见壶开了，高兴得像孩子似地叫了起来：马歇尔也看见壶开了，却悄悄地坐下来造了一不蒸汽机。