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In addition to the established energy sources such as gas, coal, oil and nuclear, there are a number of other sources that we ought to consider. Two of these are hydroelectric and tidal power.These two sources are 1 in that they are both renewable. 2 , hydropower is more widely used than tidal. In 3 , a substantial amount of electricity is already produced in HEP (hydroelectric power)stations worldwide, 4 tidal stations are still in the very early 5 of development.As far as geographical 6 is concerned, HEP projects are to be found on lakes and rivers. while tidal 7 are constructed only at river mouths where tidal 8 is great. Unfortunately these are 9 in number. At present HEP stations are found mainly in Norway, Canada, Sweden and Brazil, whereas tidal plants are in 10 in France, Russia and China.As regards capital 11 , both require very high investment. On the other hand, generating 12 are quite low in both cases. In fact, a large scale HEP plant is capable of producing power more 13 than conventional sources, such as coal, oil and nuclear plants. Tidal power also compares 14 with nuclear and oil generated electricity, 15 the amount of money on production. 16 HEP stations, tidal constructions have a long life 17 . It is estimated that they can operate for over 100 years. With respect to 18 of supply, tidal stations 19 from HEP ones in that they often can only supply power 20 . HEP stations, however, provide a constant supply of electricity.
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In addition to the established energy sources such as gas, coal, oil and nuclear, there are a number of other sources that we ought to consider. Two of these are hydroelectric and tidal power.These two sources are 1 in that they are both renewable. 2 , hydropower is more widely used than tidal. In 3 , a substantial amount of electricity is already produced in HEP (hydroelectric power)stations worldwide, 4 tidal stations are still in the very early 5 of development.As far as geographical 6 is concerned, HEP projects are to be found on lakes and rivers. while tidal 7 are constructed only at river mouths where tidal 8 is great. Unfortunately these are 9 in number. At present HEP stations are found mainly in Norway, Canada, Sweden and Brazil, whereas tidal plants are in 10 in France, Russia and China.As regards capital 11 , both require very high investment. On the other hand, generating 12 are quite low in both cases. In fact, a large scale HEP plant is capable of producing power more 13 than conventional sources, such as coal, oil and nuclear plants. Tidal power also compares 14 with nuclear and oil generated electricity, 15 the amount of money on production. 16 HEP stations, tidal constructions have a long life 17 . It is estimated that they can operate for over 100 years. With respect to 18 of supply, tidal stations 19 from HEP ones in that they often can only supply power 20 . HEP stations, however, provide a constant supply of electricity.
As West Nile virus creeps toward California, an unlikely warrior could provide the first line of defense: the chicken. The familiar fowl make irresistible targets for mosquitoes. Unlike crows, chickens don"t get sick from West Nile. But they do produce telltale antibodies to the virus. So in test coops scattered across the state, more than 2000 "sentinel chickens" submit to frequent blood tests. When antibodies do turn up, California health officials will know that the inevitable has occurred; the West Nile epidemic will have swept the country.Last week alone, more than 100 new human cases of West Nile were reported. The virus was detected as far west as Colorado and Wyoming, infecting 371 and killing 16 people in 20 states plus the District of Columbia. This year West Nile appeared earlier in the mosquito season—mid-June instead of August—and claimed younger victims ; the average age dropped from 65 to 54. Federal health officials are still trying to figure out why, but say they may be finding more West Nile precisely because they"re on the lookout for it. As Dr. Julie Gerberding, the new director of the Centers for Disease Control (CDC), recently told reporters, "We"re not in crisis mode."When West Nile hit New York City in 1999, the CDC realized it was a victim of its own success. Because health officials had conquered most mosquito-borne diseases decades ago, many states abolished their mosquito-control programs. The Feds rushed in with funds—some $50 million since 1999, plus $31 million more this year alone—to train insect researchers, set up state testing labs and kill off the annoying insects. The CDC established a new computer monitoring system and held strategy sessions with state officials.Some epidemiologists question the focus—and the millions—lavished on a virus that"s killed fewer than 20. "There"s an epidemic in gun violence that"s taking more lives than West Nile virus," says Dr. William Steinmann, director of the Tulance Center for Clinical Effectiveness and Prevention, But the Feds say their efforts have kept West Nile from doing far more damage. "We"re basically building the infrastructure to deal with this over the next 50 years," says Dr. Lyle Peterson, a CDC epidemiologist: "This is here to stay. "So far, there are no remedies for West Nile. Officials eventually expect the virus to settle into a quiet pattern of mild infections with occasional outbreaks. To do battle at home, the CDC recommends eliminating standing water and using insect spray with DEET—simple precautions, but the best defense against an invader that shows no signs of going away. Feds claimed that their spending on West Nile control was
For centuries the most valuable of African resources for Europeans were the slaves, but these could be obtained at coastal ports, without any need for going deep inland. Slavery had been an established institution in Africa. Prisoners of war had been enslaved, as were also debtors and individuals guilty of serious crimes. But these slaves usually were treated as part of the family. They had clearly defined rights, and their slave status was not necessarily inherited. Therefore it is commonly argued that Africa"s traditional slavery wasmildcompared to the trans-Atlantic slave trade organized by the Europeans. This argument, however, can be carried too far. In the most recent study of this subject, some scholars warned against the illusion that "cruel and dehumanizing enslavement was a monopoly of the West. Slavery in its extreme forms, including the taking of life, was common to both Africa and the West. The fact that African slavery had different origins and consequences should not lead us to deny what it was—the exploitation and control of human beings." Neither can it be denied that the wholesale shipment of Africans to the slave plantations of the Americas was made possible by the participation of African chiefs who rounded up their fellow Africans and sold them as a handsome profit to European ship captains waiting along the coasts.Granting all this, the fact remains that the trans-Atlantic slave trade conducted by the Europeans was entirely different in quantity and quality from the traditional type of slavery that had existed within Africa. From the beginning the European variety was primarily an economic institution rather than social, as it had been in Africa. Western slave traders and slave owners were acted on by purely economic considerations, and were quite ready to work their slaves to death if it was more profitable to do so than to treat them more mercifully. This inhumanity was reinforced by racism when the Europeans became involved in the African slave trade on a large scale. Perhaps as a subconscious rationalization they gradually came to look down on Negroes as inherently inferior, and therefore destined to serve their white masters. Rationalization also may have been involved in the Europeans" use of religion to justify the traffic in human beings. It was argued, for instance, that enslavement assured the conversion of the African evil-believing religions to the true faith as well as to civilization. Supporters of the rationalization of slavery believe that the trade
Jill Ker Conway, president of Smith, echoes the prevailing view of contemporary technology when she says that "anyone in today"s world who doesn"t understand data processing is not educated." But she insists that the increasing emphasis on these matters leave certain gaps. Says she: "The very strongly utilitarian emphasis in education, which is an effect of man-made satellites and the cold war, has really removed from this culture something that was very profound in its 18th and 19th century roots, which was a sense that literacy and learning were ends in themselves for a democratic republic."In contrast to Plato"s claim for the social value of education, a quite different idea of intellectual purposes was advocated by the Renaissance humanists. Overjoyed with their rediscovery of the classical learning that was thought to have disappeared during the Dark Ages, they argued that the imparting of knowledge needs no justification—religious, social, economic, or political. Its purpose, to the extent that it has one, is to pass on from generation to generation the corpus of knowledge that constitutes civilization. "What could man acquire, by virtuous striving, that is more valuable than knowledge" asked Erasmus, perhaps the greatest scholar of the early 16th century. That idea has acquired a tradition of its own. "The educational process has no end beyond itself," said John Dewey. "It is its own end."But what exactly is the corpus of knowledge to be passed on In simpler times, it was all included in the medieval universities" Quadrivium (arithmetic, geometry, astronomy, music) and Trivium (grammar, rhetoric, logic). As recently as the last century, when less than 5% of Americans went to college at all, students in New England establishments were compelled mainly to memorize and recite various Latin texts, and crusty professors angrily opposed the introduction of any new scientific discoveries or modern European languages. "They felt," said regretfully Charles Francis Adams, Jr., the Union Pacific Railroad president who devoted his later years to writing history," that a classical education was the important distinction between a man who had been to college and a man who had not been to college, and that anything that diminished the importance of this distinction was essentially revolutionary and tended to anarchy." It can be inferred that Charles Francis Adams, Jr.
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