The gas of gasoline is heavier than air, so a container should never be held ABOVE a flame. Keep kerosene and gasoline containers well corked and at a distance from fire.英文原著 · 《The Miracle Mongers》
I saw that for thirty years before I saw it. Did you ever notice how long you have to see most things before you see them? I saw that when I played marbles. The big marbles would shake to the top of my pocket and the little ones would rattle down to the bottom. You children try that tomorrow. Do not wait thirty years to learn that the big ones shake up and the little ones shake down. Put some big ones and some little things of about the same density in a box or other container and shake them. You will see the larger things shake upward and the smaller shake downward.英文原著 · 《The University of Hard Knocks》