Tut. You may call it so: but it is properly an operation of chymistry.
Pup. Of chymistry! I thought that had been a very deep sort of a business.
Tut. O—there are many things in common life that belong to the deepest of sciences. Making tea is the chymical operation called infusion, which is, when a hot liquor is poured upon a substance in order to extract something from it. The water, you see, extracts from the tea-leaves their colour, taste, and flavour.
Pup. Would not cold water do the same?
Tut. It would, but more slowly. Heat assists almost all liquors in their power of extracting the virtues of herbs and other substances. Thus good housewives were formerly used to boil their tea, in order to get all goodness from it as completely as possible. The greater heat and agitation of boiling make it act more powerfully. The liquor in which a substance has been boiled is called a decoction of that substance.
Pup. Then we had a decoction of mutton at dinner to-day.
Tut. We had—broth is a decoction, and so are gruel and barley-water. But when anything is put to steep in a cold liquor it is called maceration. The ingredients of which ink is made are macerated. In all these cases, you see, the whole substance does not mix with the liquor, but only part of it. The reason is, that part of it is soluble in the liquor, and part not.
Pup. What is the meaning of that?
Tut. Solution is when a solid put into a fluid entirely disappears in it, leaving the liquor clear. Thus when I throw this lump of sugar into my tea, you see it gradually wastes away till it is all gone, and then I can taste it in every single drop of my tea; but the tea is as clear as before.
Pup. Salt would do the same.