James Watt, Scottish engineer and inventor of the Watt steam engine, which was the vital technology of the Industrial Revolution in the 18th century, gained early ideas on the subject from observation of a kettle. It is said that, when Watt was a child, his aunt, Mrs Muirhead, sitting with him one evening at the tea-table, said, "James, I never saw such an idle boy! Take a book or employ yourself usefully. For the last half-hour you have not spoken a word, but taken off the lid of that kettle and put it on again, holding now a cup and now a silver spoon over the steam, while it rises from the spout, and counting the drops of water." It appears that when thus blamed he was investigating the condensation of steam.
蘇格蘭工程師詹姆斯．瓦特發明的瓦特蒸汽機，是十八世紀工業革命不可或缺的科技產品，而其初步構思，來自瓦特對水壺之觀察。據說，瓦特小時，姑母繆爾黑德太太有一晚和他一起，坐在茶几前，對他說：「詹姆斯，我從沒見過像你這麼懶惰的孩子。拿本書讀讀，或做些有意思的事吧。這半個鐘頭，你一言不發，把水壺蓋拿起又放下，見水壺嘴冒出蒸汽，就拿起茶杯、銀匙，反覆置於蒸汽之上，點算凝結的水點。」看來，瓦特受責的時候，正在研究水蒸汽怎樣凝結。