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How much of each year do spiders spend killing insects?

Why, you may wonder, should spiders be our friends? Because they destroy so many insects, and insects include some of the greatest enemies of the human race. Insects would make it impossible for us to live in the world; they would devour all our crops and kill our flocks and herds, if it were not for the protection we get

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What was the main objective of early mountain climbers?

Modern alpinists try to climb mountains by a route which will give them good sport, and the more difficult it is, the more highly it is regarded. In the pioneering days, however, this was not the case at all. The early climbers were looking for the easiest way to the top, because the summit was the prize they sought, espe

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How did Vera discover she had this gift of second sight?

Several cases have been reported in Russia recently of people who can detect colours with their fingers, and even see through solid and walls. One case concerns and eleven-year-old schoolgirl, Vera Petrova, who has normal vision but who can also perceive things with different parts of her skin, and through solid walls. This a

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How does the writer like to treat young people?

People are always talking about ‘the problem of youth’. If there is one — which I take leave to doubt — then it is older people who create it, not the young themselves. Let us get down to fundamentals and agree that the young are after all human beings — people just like their elders. There is only o

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How does the writer describe sport at the international level?

I am always amazed when I hear people saying that sport creates goodwill between the nations, and that if only the common peoples of the would could meet one another at football or cricket, they would have no inclination to meet on the hattlefield. Even if one didn’t know from concrete examples (the 1936 Olymp

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In what way does echo-location in bats play an utilitarian role?

Not all sounds made by animals serve as language, and we have only to turn to that extraordinary discovery of echo-location in bats to see a case in which the voice plays a strictly utilitarian role.

To get a full appreciation of what this means we must turn first to some recent human inventions. Everyone

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What makes trading between rich countries difficult?

Chickens slaughtered in the United States, claim officials in Brussels, are not fit to grace European tables. No, say the American: our fowl are fine, we simply clean them in a different way. These days, it is differences in national regulations, far more than tariffs, that put sand in the wheels of trade between rich countr

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What important thing did King Alfred learn when he penetrated the Danish camp of Guthrum?

Alfred the Great acted his own spy, visiting Danish camps disguised as a minstrel. In those days wandering minstrels were welcome everywhere. They were not fighting men, and their harp was their passport. Alfred had learned many of their ballads in his youth, and could vary his programme

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What does the computer industry thrive on apart from anarchy?

Technology trends may push Silicon Valley back to the future. Carver Mead, a pioneer in integrated circuits and a professor of computer science at the California Institute of Technology, notes there are now work-stations that enable engineers to design, test and produce chips right on their desks, much the way an ed