To his surprise, he discovered that the carbon in the candle wax had formed all four types of pure carbon, including diamonds and graphite, or pencil lead.
令他吃惊的是，他发现蜡烛里的碳已经形成了纯碳的四种形态，包括：钻石、石墨和铅笔芯。
2
Buy a large candle, and use a mechanical pencil with no lead in it to engrave a message.