Tut. It ascends into the air, and unites with it. But if in its way it be stopped by any cold body, it is condensed, that is, it returns to the state of water again. Lift up the lid of the teapot and you will find water collected on the inside of it, which is condensed steam from the hot tea beneath. Hold a spoon or knife in the way of the steam which bursts out of the spout of the teakettle, and you will find it immediately covered with drops. This operation of turning a fluid into vapour, and then condensing it, is called distillation. For this purpose, the vessel in which the liquor is heated is closely covered with another called the head, into which the steam rises and is condensed. It is then drawn off by means of a pipe into another vessel called the receiver. In this way all sweet-scented and aromatic liquors are drawn from fragrant vegetables, by means of water or spirits. The fragrant part being very volatile rises along with the steam of the water or spirit, and remains united with it after it is condensed. Rosewater, and spirits of lavender, are liquors of this kind.
Pup. Then the water collected on the inside of the teapot-lid should have the fragrance of the tea.
Tut. It should—but unless the tea were fine, you could scarcely perceive it.
Pup. I think I have heard of making salt water fresh by distilling.
Tut. Yes. That is an old discovery lately revived. The salt in seawater, being of a fixed nature, does not rise with the steam; and therefore, on condensing the steam, the water is found to be fresh. And this indeed is the method nature employs in raising water by exhalation from the ocean, which, collecting in clouds, is condensed in the cold region of the air, and falls down in rain.
But our tea is done: so we will now put an end to our chymical lecture.
Pup. But is this real chymistry?
Tut. Yes, it is.
Pup. Why, I understand it all without any difficulty.
Tut. I intended you should.