The growth of population during the past few centuries is no proof that population will continue to grow straight upward toward infinity and doom. On the contrary, demographic history offers evidence that population growth has not been at all constant. According to paleoecologist Edward Deevey, the past million years show three momentous changes. The first, a rapid increase in population around one m illion B. C., followed the innovations of tool making and tool using. But when the new power from the use of tools has been exploited, the rate of world population growth fell and became almost stable. The next rapid jump in population started perhaps 10,000 years ago, when mankind began to keep herds, plow and plant the earth. Once again when initial productivity gains had been absorbed, the rate of population growth abated. These two episodes suggest that the third great change, the present rapid growth, which began in the West between 250 and 350 years ago, may also slow down when, or if, technology begins to yield fewer innovations. Of course, the current knowledge revolution may continue without foreseeable end. Either way - contrary to popular belief in constant geometric growth - population can be expected in the long run to adjust to productivity. And when one takes this view, population growth is seen to represent economic progress and human triumph rather than social failure.
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July 5th, 2008 | Posted in Society | No Comments
Few institutions are more important to an urban community than its police, yet there are few subjects historians know so little about. Most of the early academic interests developed among political scientists and sociologists, who usually examined their own contemporary problems with only a nod toward the past. Even the public seemed concerned only during crime waves, periods of blatant corruption, or after a particularly grisly episode. Party regulars and reformers generally viewed the institution from a political perspective; newspapers and magazines - the nineteenth century’s media - emphasized the vivid and spectacular.
Yet urban society has always vested a wide, indeed awesome, responsibility in its police. Not only were they to maintain order, prevent crime, and protect life and property, but historically they were also to fight fires, suppress vice, assist in health services, supervise elections, direct traffic, inspect buildings, and locate truants and runaways. In addition, it was assumed that the police were the special guardians of the citizens’ liberties and the community’s tranquillity. Of course, the performance never matched expectations. The record contains some success, but mostly failure; some effective leadership, but largely official incompetence and betrayal. The notion of a professional police force in America is a creation of the twentieth century; not until our own time have cities begun to take the steps necessary to produce modern departments.
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July 5th, 2008 | Posted in Society | No Comments
Mars According to the best evidence gathered by space probes and astronomers, Mars is an inhospitable planet, more similar to Earth’s Moon than to Earth itself - a dry, stark, seemingly lifeless world. Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet. The air there is 95% carbon dioxide. Mars has no ozone layer to screen out the Sun’s lethal radiation. Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space. Even at the equator, the temperature drops to 50℃ ( 60 ) at night. Today there is no liquid water, although valleys and channels on the surface show evidence of having been carved by running water. The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost. Despite these difficult conditions, certain scientists believe that there is a possibility of transforming Mars into a more Earth like planet. Nuclear reactors might be used to melt frozen gases and eventually build up the atmosphere. This in turn could create a “greenhouse effect” that would stop heat from radiating back into space. Liquid water could be thawed to form a polar ocean. Once enough ice has melted, suitable plants could be introduced to build up the level of oxygen in the atmosphere so that, in time, the planet would support animal life from Earth and even permanent human colonies. “This was once thought to be so far in the future as to be irrelevant,” said Christopher McKay, a research scientist at the National Aeronautics and Space Administration. “But now it’s starting to look practical. We could begin work in four or five decades.” The idea of “terra forming” Mars, as enthusiasts call it, has its roots in science fiction. But as researchers develop a more profound understanding of how Earth’s ecology supports life, they have begun to see how it may be possible to create similar conditions on Mars. Don’t plan on homesteading on Mars any time soon, though. The process could take hundreds or even thousands of years to complete, and the cost would be staggering.
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July 5th, 2008 | Posted in Space | No Comments
Hydrogen, the lightest and simplest of the elements, has several properties that make it valuable for many industries. It releases more heat per unit of weight than any other fuel. In rocket engines, tons of hydrogen and oxygen are burned, and hydrogen is used with oxygen for welding torches that produce temperatures as high as 4, 000 degrees F and can be used in cutting steel. Fuel cells to generate electricity operate on hydrogen and oxygen.
Hydrogen also serves to prevent metals from tarnishing during heat treatments by removing the oxygen from them. Although it would be difficult to remove the oxygen by itself, hydrogen readily combines with oxygen to form water, which can be heated to steam and easily removed.
Hydrogen is also useful in the food industry for a process know as hydrogenation. Products such as margarine and cooking oils are changed from liquids to semisolids by adding hydrogen to their molecules. Soap manufacturers also use hydrogen for this purpose.
Hydrogen is also one of the coolest refrigerants. It does not become a liquid until it reaches temperatures of -425 degrees F. Pure hydrogen gas is used in large electric generators to cool the coils. In addition, in the chemical industry, hydrogen is used to produce ammonia, gasoline, methyl alcohol, and many other important products.
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July 5th, 2008 | Posted in Science | No Comments
Chemistry did not emerge as a science until after the scientific revolution in the seventeenth century and then only rather slowly and laboriously. But chemical knowdedge is as old as history, being almost entirely concerned with the practical arts of living. Cooking is essentially a chemical process; so is the melting of metals and the administration of drugs and poisons. This basic chemical knowledge, which was applied in most cases as a rule of thumb, was nevertheless dependent on previous experiment. It also served to stimulate a fundamental curiosity about the processes themselves. New information was always being gained as artisans improved techniques to gain better results. The development of a scientific approach to chemistry was, however, hampered by several factors. The most serious problem was the vast range of material available and the consequent difficulty of organizing it into some system. In addition, there were social and intellectual difficulites, chemistry is nothing if not practical; those who practice it must use their hands, they must have a certain practical flair. Yet in many ancient civilizations, practical tasks were primarily the province of a slave population. The thinker or philosopher stood apart from this mundane world, where the practical arts appeared to lack any intellectual content or interest. The final problem for early chemical science was the element of secrecy. Experts in specific trades had developed their own techniques and guarded their knowledge to prevent others from stealing their livelihood. Another factor that contributed to secrecy was the esoteric nature of the knowledge of a alchemists, who were trying to transform base metals into gold or were concerned with the hunt for the elixir that would bestow the blessing of eternal life. In one sense, the second of these was the more serious impediment because the records of the chemical processes that early alchemists had discovered were often written down in symbolic language intelligible to very few or in symbols that were purposely obscure.
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July 5th, 2008 | Posted in Science | No Comments
Each advance in microscopic technique has provided scientists with new perspectives on the function of living organisms and the nature of matter itself. The invention of the visible light microscope late in the sixteenth century introduced a previously unknown realm of single celled plants and animals. In the twentieth century, electron microscopes have provided direct views of viruses and minuscule surface structures. Now another type of microscope, one that utilizes x rays rather than light or electrons, offers a different way of examining tiny details; it should extend human perception still farther into the natural world. The dream of building an x ray microscope dates to back 1895; its development, however was virtually halted in the 1940’s because the development of the electron microscope was progressing rapidly. During the 1940’s, electron microscopes routinely achieved resolution better than that poss ible with a visible light microscope, while the performance of x ray microscopes resisted improvement. In recent years, however, interest in x ray microscopes has revived, largely because of advances such as the developmen t of new sources of x ray illumination. As a result, the brightness available today is millions of times tha t of x ray tubes, which, for most of the century, were the only available sources of soft x rays.The new x ray microscopes considerably improve on the resolution provided by optical microscopes. They can also be used to map the distribution of certain chemical elements. Some can form pictures in extremely short times; others hold the promise of special capabilities such as three dimensional imaging. Unlike conventional electron microscope, x ray microscope enables specimens to be kept in air and in water, which means that biological samples can be studied under conditions similar to their natural state. The illumination used, so called soft x rays in the wavelength range of twenty to forty angstroms (an angstrom is one ten billionth of a meter), is also sufficiently penetrating to image intact biological cells in ma ny cases. Because of the wavelength of the x rays used, soft x ray microscopes will never match the highest resolution possible with electron microscopes. Rather, their special properties will make possible investigations that will complement those performed with light and electron based instruments.
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July 5th, 2008 | Posted in Science | No Comments
Perhaps the most striking quality of satiric literature is its freshness, its originality of perspective. Satire rarely offers original ideas. Instead, it presents the familiar in a new form. Satirists do not offer the world new philosophies. What they do is to look at familiar conditions from a perspective that makes these conditions seem foolish, harmful, or affected. Satire jars us out of complacence into a pleasantly shocked realization that many of the values we unquestioningly accept are false. Don Quixote derides the stupidity of knights Brave New World ridicules the pretensions of science; A Modest Proposal dramatizes starvation by advocating cannibalism. None of these ideas is original. Chivalry was suspect before Cervantes, humanists objected to the claims of pure science before Aldous Huxley, and people were aware of famine before Swift. It was not the originality of the idea that made these satires popular. It was the manner of expression, the satiric method that made them interesting and entertaining. Satires are read because they are aesthetically satisfying works of art, not because they are morally wholesome or ethically instructive. They are stimulating and refreshing because with commonsense briskness they brush away illusions and secondhand opinions. With spontaneous irreverence, satire rearranges perspectives, scrambles familiar objects into incongruous juxtaposition, and speaks in a personal idiom instead of abstract platitude.
Satire exists because there is need for it. It has lived because readers appreciate a refreshing stimulus, an irreverent reminder that they live in a world of platitudinous thinking, cheap moralizing, and foolish philosophy. Satire serves to prod people into an awareness of truth, though rarely to any action on behalf of truth. Satire tends to remind people that much of what they see, hear, and read in popular media is sanctimonious, sentimental, and only partially true. Life resembles in only a slight degree the popular image of it. Soldiers rarely hold the ideals that movies attribute to them, nor do ordinary citizens devote their lives to unselfish service of humanity. Intelligent people know these things but tend to forget them when they do not hear them expressed.
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July 5th, 2008 | Posted in Literature | No Comments
The Alaska pipeline starts at the frozen edge of the Arctic ocean. It stretches southward across the largest and northernmost state in the United States, ending at a remote ice free seaport village nearly 800 miles from where it begins. It is massive in size and extremely complicated to operate. The steel pipe crosses windswept plains and endless miles of delicate tundra that tops the frozen ground. It weaves through crooked canyons, climbs sheer mountains, plunges over rocky crags, makes its way through thick forests, and passes over or under hundreds of rivers and streams. The pipe is 4 feet in diameter, and up to 2 million barrels (or 84 million gallons) of crude oil can be pumped through it daily. Resting on H shaped steel racks called “bents”, long sections of the pipeline follow a zigzag course high above the frozen earth. Other long sections drop out of sight beneath spongy or rocky ground and return to the surface later on. The pattern of the pipeline’s up and down route is determined by the often harsh demands of the Arctic and subarctic climate, the tortuous lay of the land, and the varied compositions of soil, rock, or permafrost(permanently frozen ground). A little more than half of the pipeline is elevated above the ground. The remainder is buried anywhere from 3 to 12 feet, depending largely upon the type of terrain and the properties of the soil. One of the largest in the world, the pipeline cost approximately ＄8 billion and is by far the biggest and most expensive construction project ever undertaken by private industry. In fact, no single business could raise that much money, so 8 major oil companies formed a consortium in order to share the costs. Each company controlled oil rights to particular shares of land in the oil fields and paid into the pipeline construction fund according to the size of its holdings. Today, despite enormous problems of climate, supply shortages, equipment breakdowns, labor disagreements, treacherous terrain, a certain amount of mismanagement, and even theft, the Alaska pipeline has been completed and is operating.
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July 5th, 2008 | Posted in Society | No Comments
Carmen Lomas Garza’s eloquent etchings, lithographs, and gouache paintings depict primal images of the rural environment and communal cultural experience of Mexican decended people in the United States. In an introspective and personal language, she describes the customs, traditions, a nd ways of life of her Texan Mexican heritage.By 1972, Lomas Garza had evolved her distinctive monitos, paintings of stylized figures in culturally specific social environments. She transposes images and scenes from her past, combining cultural documentation with invention in an interplay of fact and fiction. Through selection, emphasis, and creation, these monitos delineate facets of experience, expressing deeper truths. Oral tradition is a mainstay of Chicano culture. In both urban and rural communities, a rich and varied repertoire of ballads, tales, and poetic forms is preserved in memory and passed from generation to generation. Lomas Garza’s monitos function as an oral tradition in visual form. Her unique art of storytelling employs iconographic elements to create a concentrated narration. Visual episodes within an unfolding epic tale of cultural regeneration, the monitos keep alive the customs and daily practices that give meaning and coherence to Chicano identity. Their basic aim is to delight and instruct. For those outside Chicano culture, the precise and minutely detail ed monitos provide a glimpse into the rich and vibrant lifestyl e of the largest Spanish speaking cultural group within the United States society. Although her art has an innocent earnestness and folkloric affinity, Lomas Garza’s expression is neither naive nor instinctive. The artist is highly trained academically, but has chosen to remain independent of dominant artistic trends in order to work toward a private aesthetic response to social concerns. While her work does not posit an overt political statement, it originates from a desire to respo nd to the contemporary situation of Mexican Americans by expressing positive images of their culture.
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July 5th, 2008 | Posted in art | No Comments
To produce the upheaval in the United States that changed and modernized the domain of higher education from the mid 1860’s to the mid 1880’s, three primary causes interacted. The emergence of a half dozen leaders in education provided the personal force that was needed. Moreover, an outcry for a fresher, more practical, and more advanced kind of instruction arose among the alumni and friends of nearly all of the old colleges and grew into a movement that overrode all conservative opposition. The aggressive “Young Yale” movement appeared, demanding partial alumni control, a more liberal spirit, and a broader course of study. The graduates of Harvard college simultaneously rallied to relieve the college’s poverty and demand new enterprise. Education was pushing toward higher standards in the East by throwing off church leadership everywhere, and in the West by finding a wider range of studies and a new sense of public duty. The old style classical education received its most crushing blow in the citadel of Harvard College, where Dr. Charles Eliot, a young captain of thirty five, son of a former treasurer of Harvard, led the progressive forces. Five revolutionary advances were made during the first years of Dr. Eliot’s administration. They were the elevation and amplification of entrance requirements, the enlargement of the curriculum and the development of the elective system, the recognition of graduate study in the liberal arts, the raising of professional training in law, medicine, and engineering to a postgraduate level, and the fostering of greater maturity in students’ life. Standards of admission were sharply advanced in 1872-1873 and 1876-1877. By the appointment of a dean to take charge of student affairs, and a wise handling of discipline, the undergraduates were led to regard themselves more as young gentlemen and less as young animals. One new course of study after another was opened up - science, music, the history of the fine arts, advanced Spanish, political economy, physics, classical philology, and international law.
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July 5th, 2008 | Posted in Education | No Comments
