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In many ways college students of the last two decades of the nineteenth century wore inextricably involved in the processes of change. The North American institutions the attended were undergoing profound transformation. It was not just that more students were being admitted. These were different students -some were women . In Ontario, Canada, Queen's University was the first to admit women into degree programs , and the University of Toronto followed suit eight years later in 1884, Moreover, as colleges ceased to cater more narrowly to candidates for the religious ministry and the professions and came to be seen as a logical continuation of secondary school, younger students began to predominate. Many of those who now enrolled were experiencing transition not only from a small town or rural area to an urban environment , but also from adolescence to young adulthood . Universities had to adjust to the needs of students who were less mature and less settled in their interests . As the student body change, so did the curriculum. Scientific, professional, and graduate training became much more sophisticated, but the traditional arts program was altered as well. Rigid courses of study full of Greek and Latin prerequisites were being replaced at many schools by elective systems that featured new subjects, such as English literature , political science, economics, sociology, and psychology. Old subjects, like biology and philosophy , were rocked by new ideas, so that they too seemed very different. 重点单词： A painter hangs his or her finished picture on a wall , and everyone can see it . A composer writes a work, but no one can hear it until it is performed . Professional singers and players have great responsibilities , for the composer is utterly dependent on them. A student of music needs as long and as arduous a training to become a performer as a medical student needs to become a doctor. Most training is concerned with technique ,for musicians have to have the muscular proficiency of an athlete or a ballet dancer. Singers practice breathing every day ,as their vocal chords would be inadequate without controlled muscular support .String players practice moving the fingers of the left hand up and down. While drawing the bow to and fro with the right arm---two entirely different movements. Singers and instrumentalists have to be able to get every note perfectly in tune. Pianists are spared this particular anxiety, for the notes are already there , waiting for them ,and it is the piano tuner's responsibility to tune the instrument for them. But they have their own difficulties : the hammers that hit the strings have to be coaxed not to sound like percussion, and each overlapping tone has to sound clear . This problem of getting clear texture is one that confronts student conductors: they have to learn to know every note of the music and how it should sound , and they have to aim at controlling these sounds with fanatical but selfless authority. Technique is of no use unless it is combined with musical knowledge and understanding. Great artists are those who are so thoroughly at home in the language of music that they can enjoy performing works written in any century. 重点单词： Nitinol is one of the most extraordinary metals to be discovered this century. A simple alloy of nickel and titanium , nitinol has some perplexing properties . A metal with a memory , it can be made to remember any shape into which it is fashioned , returning to shape whenever it is heated. For example, a piece of nitinol wire bent to form a circle that is then heated and quenched will remember this shape. It may then be bent or crumpled, but on reheating , will violently untwist, reforming its original shape. This remarkable ability is called Shape Memory Effect (SME) : other alloys, such as brasses, are known to posses it to a limited extent. No one fully understands SME, and nitinol remains particularly perplexing, for , whenever it performs this peculiar feat, it appears to be breaking the laws of thermodynamics by springing back into shape with greater force than was used to deform it in the first place. But not only is nitinol capable of remembering. It also has the ability to "learn". If the heating -cooling -crumpling -reheating process is carried out sufficiently often, and the metal is always crumpled in exactly the same way, the nitinol will not only remember its original shape, but gradually it learns to remember its crumpled form as well , and will begin to return to the same crumpled shape every time it is cooled . Eventually , the metal will crumple and uncrumple, totally unaided , in response to changes in temperature and without any sign of metal fatigue . Engineers have produced prototype engines that are driven by the force of nitinol springing from one shape to another as it alternately encounters hot and cold water. The energy from these remarkable engines is, however, not entirely free: heat energy is required to produce the temperature differences needed to run the engine. But the optimum temperatures at which the metal reacts can be controlled by altering the proportions of nickel to titanium: some alloys will even perform at room temperature. The necessary temperature range between the warm and the cold can be as little as twelve degrees centigrade. Technique is of no use unless it is combined with musical knowledge and understanding. Great artists are those who are so thoroughly at home in the language of music that they can enjoy performing works written in any century. 重点单词： With a literary history that goes back as far as the seventeenth century , Florida has long been a major for writers from all over the United States. Jonathan Dickinson, whose group of Quakers was cast up on the coast near what is now Palm Beach after they were wrecked on route from Jamaica to Pennsylvania, recorded the tragedy in God's Protecting Providence in 1699. Not only was this book one of America's first best-sellers , but it was also the first account of the American Indians of the southeastern coast. Other early writers who followed Dickinson celebrated the rich and various plant and animal life of the region, striking sympathetic chords in the imaginations of Ralph Waldo Emerson and the English poets William Wordsworth and Samuel Taylor Coleridge . Florida has been visited by many writers who sometimes were so taken by what they saw that they adopted it as their home. Harriet Stowe , the author of Uncle Tom's Cabin, spent several winters on an orange farm that she and her husband bought in 1867. The Stowes' original intent in buying a home, which is at Mandarin on the Saint Johns River, was to create a model for the employment of former slaves. The original intent had to give way to other considerations .So many spectators flocked of form to catch a glimpse of Mrs. Stowe that a charge of 25 cents per person for admission was established. On his way to report on the Cuban Revolution in 1896, Stephen Crane spent some time in Jacksonville. It was there that Crane met his wife , who at that time ran a popular tavern in the town. On his way to Cuba, Crane's boat sank off the coast of Florida , and incident that provided Crane with the material on which his masterpiece "The Open Boat" is based. James Weldon Johnson ,a prominent Black author, was a native of Florida. He was born in Jacksonville in 1871 and was a songwriter. poet, novelist , teacher , and the first Black man to become a lawyer in Florida since the Reconstruction . Johnson also fought successfully to upgrade the quality of education for Black people in Florida. 重点单词： The concept of obtaining fresh water from icebergs that are towed to populated areas and arid regions of the world was once treated as a joke more appropriate to cartoons than real life. But now it is being considered quite seriously by many nations, especially since scientists have warned that the human race will outgrow its fresh water supply faster than it runs out of food . Glaciers are a possible source of fresh water that have been overlooked until recently . Three-quarters of the Earth's fresh water supply is still tied up in glacial ice, a reservoir of untapped fresh water so immense that it could sustain all the rivers of the world for 1,000 years. Floating in the oceans every year are 7,659 trillion metric tons of ice encased in 10,000 icebergs that break away from the polar ice caps, more than ninety percent of them from Antarctica. Huge glaciers that stretch over the shallow continental shelf give birth to icebergs throughout the year. Icebergs are not like sea ice ,which is formed when the sea itself freezes ;rather ,they are formed entirely on land , breaking off when glaciers spread over the sea . As they drift away from the polar region , icebergs sometimes move mysteriously in a direction opposite to the wind, pulled by subsurface currents . Because they melt more slowly than smaller pieces of ice ,icebergs have been known to drift as far north as 35 degrees south of the equator in the Atlantic Ocean. To corral them and steer them to parts of the world where they are needed would not be too difficult. The difficulty arises in other technical matters, such as the prevention of rapid melting in warmer climates and the funneling of fresh water to shore in great volume. But even if the icebergs lost half of their volume in towing . the water they could provide would be far cheaper than that produced by desalination , or removing salt from water. 重点单词： |
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