And the more carefully we study them, the heavier we find the price that has to be paid for any temporary relief or enjoyment which they may seem to give.
Tea, Coffee, and Cocoa.

The "weakest" and most commonly used of these beverages or amusement foods, are tea, coffee, and cocoa.

These have an agreeable taste, mildly stimulate the nervous system, and, when used in moderation by adults, seldom do much harm.

To a small percentage of individuals, who are specially sensitive to their effects, they seem to act as mild poison-foods, much in the same way as strawberries, cheese, or lobsters do to others.
Tea is made from the green leaves of a shrub growing in hilly districts in China, Japan, and Southern India.

The finer and more delicately flavored brands are from the young leaves, shoots, and flowers of the plant; while the coarser and cheaper are from the old leaves, stalks, and even twigs--the latter containing the most _tannin_, which, as we shall see, is the most injurious element in tea.
Coffee is made from the seeds of a cherry-like berry growing upon a shrub, or low tree, on tropical hillsides.