Nowadays everybody must be familiar with the words "pollution" and "population". They are so well-known that they form the subject of many a polite dinner-table discussion. The assembled company will nod its heads wisely and agree that "Something must be done. " Or perhaps a short argument will ensue: For there are those who will claim that these problems have been exaggerated, who will laugh mockingly at the people they call "doomsday ecologists".
66. ______
Poisonous fumes from factories have sometimes made acres of surrounding land barren. Nor is the problem confined to land. Tons and tons of untreated sewage and unfiltered chemical waste are pumped daily into rivers and the sea, and dead fish are often to be seen floating in the water and washed up on the shores of seas, lakes and streams, while lethal oil slicks floating on the surface of the sea bring death to millions of seabirds. Meanwhile, we are cheerfully us
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