Acid rain occurs when polluting gasses become trapped in clouds that drift for hundreds, even thousands, of miles and are finally released as acidic precipitation. Trees, lakes, animals, and even buildings are vulnerable to the slow corrosive effects of acid rain, whose damaging components are emitted by power plants and factories burning low grades of coal and oil.

Acid rain was first recognized in 1872, approximately one hundred years after the beginning of the Industrial Revolution, when an English scientist, Robert Angus Smith (1817-1884), pointed out the problem. Almost another century passed, however, before the public became aware of the damaging effects of acid rain. In 1962, the Swedish scientist Svante Oden brought the acid rain quandary to the attention of the press, instead of the less popular scientific journals. He compiled records from the 1950s indicating that acid rain came from air masses moving out of central...