Taken in reasonable amounts, tea can not be said to be hurtful; and the medium qualities, carefully prepared, often make a more wholesome tea than that of the highest price, the harmful properties being strongest in the best.

If the water is soft, it should be used as soon as boiled, boiling causing all the gases which give flavor to water to escape.

In hard water, boiling softens it.

In all cases the water must be fresh, and poured boiling upon the proper portion of tea,--the teapot having first been well scalded with boiling water.

Never boil any tea but English-breakfast tea; for all others, simple steeping gives the drink in perfection.
A disregard of these rules gives one the rank, black, unpleasant infusion too often offered as tea; while, if boiled in tin, it becomes a species of slow poison,--the tannic acid in the tea acting upon the metal, and producing a chemical compound whose character it is hard to determine.
Various other plants possess the essential principle of tea, and are used as such; as in Paraguay, where the Brazilian holly is dried, and makes a tea very exhilarating in quality, but much more astringent.
The use of _Coffee_ dates back even farther than that of tea.