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新东方背诵文选全集

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新东方背诵文选全集

01 The Language of Music

A painter hangs his or her finished pictures 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 instruments 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 string 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.

02 Schooling and Education

It is commonly believed in United States that school is where people go to
get an education. Nevertheless, it has been said that today children
interrupt their education to go to school. The distinction between schooling
and education implied by this remark is important.

Education is much more open-ended and all-inclusive than schooling.
Education knows no bounds. It can take place anywhere, whether in the shower
or in the job, whether in a kitchen or on a tractor. It includes both the
formal learning that takes place in schools and the whole universe of
informal learning. The agents of education can range from a revered
grandparent to the people debating politics on the radio, from a child to a
distinguished scientist. Whereas schooling has a certain predictability,
education quite often produces surprises. A chance conversation with a
stranger may lead a person to discover how little is known of other
religions. People are engaged in education from infancy on. Education, then,
is a very broad, inclusive term. It is a lifelong process, a process that
starts long before the start of school, and one that should be an integral
part of one’s entire life.

Schooling, on the other hand, is a specific, formalized process, whose
general pattern varies little from one setting to the next. Throughout a
country, children arrive at school at approximately the same time, take
assigned seats, are taught by an adult, use similar textbooks, do homework,
take exams, and so on. The slices of reality that are to be learned, whether
they are the alphabet or an understanding of the working of government, have
usually been limited by the boundaries of the subject being taught. For
example, high school students know that there not likely to find out in
their classes the truth about political problems in their communities or
what the newest filmmakers are experimenting with. There are definite
conditions surrounding the formalized process of schooling.

03 The Definition of “Price”

Prices determine how resources are to be used. They are also the means by
which products and services that are in limited supply are rationed among
buyers. The price system of the United States is a complex network composed
of the prices of all the products bought and sold in the economy as well as
those of a myriad of services, including labor, professional,
transportation, and public-utility services. The interrelationships of all
these prices make up the “system” of prices. The price of any particular
product or service is linked to a broad, complicated system of prices in
which everything seems to depend more or less upon everything else.

If one were to ask a group of randomly selected individuals to define
“price”, many would reply that price is an amount of money paid by the
buyer to the seller of a product or service or, in other words that price is
the money values of a product or service as agreed upon in a market
transaction. This definition is, of course, valid as far as it goes. For a
complete understanding of a price in any particular transaction, much more
than the amount of money involved must be known. Both the buyer and the
seller should be familiar with not only the money amount, but with the
amount and quality of the product or service to be exchanged, the time and
place at which the exchange will take place and payment will be made, the
form of money to be used, the credit terms and discounts that apply to the
transaction, guarantees on the product or service, delivery terms, return
privileges, and other factors. In other words, both buyer and seller should
be fully aware of all the factors that comprise the total “package” being
exchanged for the asked-for amount of money in order that they may evaluate
a given price.

04 Electricity

The modern age is an age of electricity. People are so used to electric
lights, radio, televisions, and telephones that it is hard to imagine what
life would be like without them. When there is a power failure, people grope
about in flickering candlelight, cars hesitate in the streets because there
are no traffic lights to guide them, and food spoils in silent
refrigerators.

Yet, people began to understand how electricity works only a little more
than two centuries ago. Nature has apparently been experimenting in this
field for million of years. Scientists are discovering more and more that
the living world may hold many interesting secrets of electricity that could
benefit humanity.

All living cell send out tiny pulses of electricity. As the heart beats, it
sends out pulses of record; they form an electrocardiogram, which a doctor
can study to determine how well the heart is working. The brain, too, sends
out brain waves of electricity, which can be recorded in an
electroencephalogram. The electric currents generated by most living cells
are extremely small - often so small that sensitive instruments are needed
to record them. But in some animals, certain muscle cells have become so
specialized as electrical generators that they do not work as muscle cells
at all. When large numbers of these cell are linked together, the effects
can be astonishing.

The electric eel is an amazing storage battery. It can seed a jolt of as
much as eight hundred volts of electricity through the water in which it
live. (An electric house current is only one hundred twenty volts.) As many
as four-fifths of all the cells in the electric eel’s body are specialized
for generating electricity, and the strength of the shock it can deliver
corresponds roughly to length of its body.

05 The Beginning of Drama

There are many theories about the beginning of drama in ancient Greece. The
on most widely accepted today is based on the assumption that drama evolved
from ritual. The argument for this view goes as follows. In the beginning,
human beings viewed the natural forces of the world-even the seasonal
changes-as unpredictable, and they sought through various means to control
these unknown and feared powers. Those measures which appeared to bring the
desired results were then retained and repeated until they hardened into
fixed rituals. Eventually stories arose which explained or veiled the
mysteries of the rites. As time passed some rituals were abandoned, but the
stories, later called myths, persisted and provided material for art and
drama.

Those who believe that drama evolved out of ritual also argue that those
rites contained the seed of theater because music, dance, masks, and
costumes were almost always used, furthermore, a suitable site had to be
provided for performances and when the entire community did not participate,
a clear division was usually made between the "acting area" and the
"auditorium." In addition, there were performers, and, since considerable
importance was attached to avoiding mistakes in the enactment of rites,
religious leaders usually assumed that task. Wearing masks and costumes,
they often impersonated other people, animals, or supernatural beings, and
mimed the desired effect-success in hunt or battle, the coming rain, the
revival of the Sun-as an actor might. Eventually such dramatic
representations were separated from religious activities.

Another theory traces the theater’s origin from the human interest in
storytelling. According to this vies tales (about the hunt, war, or other
feats) are gradually elaborated, at first through the use of impersonation,
action, and dialogue by a narrator and then through the assumption of each
of the roles by a different person. A closely related theory traces theater
to those dances that are primarily rhythmical and gymnastic or that are
imitations of animal movements and sounds.

06 Televisions

Television-----the most pervasive and persuasive of modern technologies,
marked by rapid change and growth-is moving into a new era, an era of
extraordinary sophistication and versatility, which promises to reshape our
lives and our world. It is an electronic revolution of sorts, made possible
by the marriage of television and computer technologies.

The word "television", derived from its Greek (tele: distant) and Latin
(visio: sight) roots, can literally be interpreted as sight from a distance.
Very simply put, it works in this way: through a sophisticated system of
electronics, television provides the capability of converting an image
(focused on a special photoconductive plate within a camera) into electronic
impulses, which can be sent through a wire or cable. These impulses, when
fed into a receiver (television set), can then be electronically
reconstituted into that same image.

Television is more than just an electronic system, however. It is a means of
expression, as well as a vehicle for communication, and as such becomes a
powerful tool for reaching other human beings.

The field of television can be divided into two categories determined by its
means of transmission. First, there is broadcast television, which reaches
the masses through broad-based airwave transmission of television signals.
Second, there is nonbroadcast television, which provides for the needs of
individuals or specific interest groups through controlled transmission
techniques.

Traditionally, television has been a medium of the masses. We are most
familiar with broadcast television because it has been with us for about
thirty-seven years in a form similar to what exists today. During those
years, it has been controlled, for the most part, by the broadcast networks,
ABC, NBC, and CBS, who have been the major purveyors of news, information,
and entertainment. These giants of broadcasting have actually shaped not
only television but our perception of it as well. We have come to look upon
the picture tube as a source of entertainment, placing our role in this
dynamic medium as the passive viewer.

07 Andrew Carnegie

Andrew Carnegie, known as the King of Steel, built the steel industry in the
United States, and, in the process, became one of the wealthiest men in
America. His success resulted in part from his ability to sell the product
and in part from his policy of expanding during periods of economic decline,
when most of his competitors were reducing their investments.

Carnegie believed that individuals should progress through hard work, but he
also felt strongly that the wealthy should use their fortunes for the
benefit of society. He opposed charity, preferring instead to provide
educational opportunities that would allow others to help themselves. "He
who dies rich, dies disgraced," he often said.

Among his more noteworthy contributions to society are those that bear his
name, including the Carnegie Institute of Pittsburgh, which has a library, a
museum of fine arts, and a museum of national history. He also founded a
school of technology that is now part of Carnegie-Mellon University. Other
philanthropic gifts are the Carnegie Endowment for International Peace to
promote understanding between nations, the
Carnegie Institute of Washington to fund scientific research, and Carnegie
Hall to provide a center for the arts.

Few Americans have been left untouched by Andrew Carnegie’s generosity. His
contributions of more than five million dollars established 2,500 libraries
in small communities throughout the country and formed the nucleus of the
public library system that we all enjoy today.

08 American Revolution

The American Revolution was not a sudden and violent overturning of the
political and social framework, such as later occurred in France and Russia,
when both were already independent nations. Significant changes were ushered
in, but they were not breathtaking. What happened was accelerated evolution
rather than outright revolution. During the conflict itself people went on
working and praying, marrying and playing. Most of them were not seriously
disturbed by the actual fighting, and many of the more isolated communities
scarcely knew that a war was on.

America’s War of Independence heralded the birth of three modern nations.
One was Canada, which received its first large influx of English-speaking
population from the thousands of loyalists who fled there from the United
States. Another was Australia, which became a penal colony now that America
was no longer available for prisoners and debtors. The third newcomer-the
United States-based itself squarely on republican principles.

Yet even the political overturn was not so revolutionary as one might
suppose. In some states, notably Connecticut and Rhode Island, the war
largely ratified a colonial self-rule already existing. British officials,
everywhere ousted, were replaced by a home-grown governing class, which
promptly sought a local substitute for king and Parliament.

09 Suburbanization

If by "suburb" is meant an urban margin that grows more rapidly than its
already developed interior, the process of suburbanization began during the
emergence of the industrial city in the second quarter of the nineteenth
century. Before that period the city was a small highly compact cluster in
which people moved about on foot and goods were conveyed by horse and cart.
But the early factories built in the 1840’s were located along waterways
and near railheads at the edges of cities, and housing was needed for the
thousands of people drawn by the prospect of employment. In time, the
factories were surrounded by proliferating mill towns of apartments and row
houses that abutted the older, main cities. As a defense against this
encroachment and to enlarge their tax bases, the cities appropriated their
industrial neighbors. In 1854, for example, the city of Philadelphia annexed
most of Philadelphia County. Similar municipal maneuvers took place in
Chicago and in New York. Indeed, most great cities of the United States
achieved such status only by incorporating the communities along their
borders.

With the acceleration of industrial growth came acute urban crowding and
accompanying social stress-conditions that began to approach disastrous
proportions when, in 1888, the first commercially successful electric
traction line was developed. Within a few years the horse-drawn trolleys
were retired and electric streetcar networks crisscrossed and connected
every major urban area, fostering a wave of suburbanization that transformed
the compact industrial city into a dispersed metropolis. This first phase of
mass-scale suburbanization was reinforced by the simultaneous emergence of
the urban Middle Class, whose desires for homeownership in neighborhoods far
from the aging inner city were satisfied by the developers of single-family
housing tracts.

10 Types of Speech

Standard usage includes those words and expressions understood, used, and
accepted by a majority of the speakers of a language in any situation
regardless of the level of formality. As such, these words and expressions
are well defined and listed in standard dictionaries. Colloquialisms, on the
other hand, are familiar words and idioms that are understood by almost all
speakers of a language and used in informal speech or writing, but not
considered appropriate for more formal situations. Almost all idiomatic
expressions are colloquial language. Slang, however, refers to words and
expressions understood by a large number of speakers but not accepted as
good, formal usage by the majority. Colloquial expressions and even slang
may be found in standard dictionaries but will be so identified. Both
colloquial usage and slang are more common in speech than in writing.

Colloquial speech often passes into standard speech. Some slang also passes
into standard speech, but other slang expressions enjoy momentary popularity
followed by obscurity. In some cases, the majority never accepts certain
slang phrases but nevertheless retains them in their collective memories.
Every generation seems to require its own set of words to describe familiar
objects and events. It has been pointed out by a number of linguists that
three cultural conditions are necessary for the creation of a large body of
slang expressions. First, the introduction and acceptance of new objects and
situations in the society; second, a diverse population with a large number
of subgroups; third, association among the subgroups and the majority
population.

Finally, it is worth noting that the terms "standard" "colloquial" and
"slang" exist only as abstract labels for scholars who study language. Only
a tiny number of the speakers of any language will be aware that they are
using colloquial or slang expressions. Most speakers of English will, during
appropriate situations, select and use all three types of expressions.

11 Archaeology

Archaeology is a source of history, not just a bumble auxiliary discipline.
Archaeological data are historical documents in their own right, not mere
illustrations to written texts, Just as much as any other historian, an
archaeologist studies and tries to reconstitute the process that has created
the human world in which we live - and us ourselves in so far as we are each
creatures of our age and social environment. Archaeological data are all
changes in the material world resulting from human action or, more
succinctly, the fossilized results of human behavior. The sum total of these
constitutes what may be called the archaeological record. This record
exhibits certain peculiarities and deficiencies the consequences of which
produce a rather superficial contrast between archaeological history and the
more familiar kind based upon written records.

Not all human behavior fossilizes. The words I utter and you hear as
vibrations in the air are certainly human changes in the material world and
may be of great historical significance. Yet they leave no sort of trace in
the archaeological records unless they are captured by a Dictaphone or
written down by a clerk. The movement of troops on the battlefield may
"change the course of history," but this is equally ephemeral from the
archaeologist’s standpoint. What are perhaps worse, most organic materials
are perishable. Everything made of wood, hide, wool, linen, grass, hair, and
similar materials will decay and vanish in dust in a few years or centuries,
save under very exceptional conditions. In a relatively brief period the
archaeological record is reduce to mere scraps of stone, bone, glass, metal,
and earthenware. Still modern archaeology, by applying appropriate
techniques and comparative methods, aided by a few lucky finds from
peat-bogs, deserts, and frozen soils, is able to fill up a good deal of the
gap.

12 Museums

From Boston to Los Angeles, from New York City to Chicago to Dallas, museums
are either planning, building, or wrapping up wholesale expansion programs.
These programs already have radically altered facades and floor plans or are
expected to do so in the not-too-distant future.

In New York City alone, six major institutions have spread up and out into
the air space and neighborhoods around them or are preparing to do so.

The reasons for this confluence of activity are complex, but one factor is a
consideration everywhere - space. With collections expanding, with the needs
and functions of museums changing, empty space has become a very precious
commodity.

Probably nowhere in the country is this more true than at the Philadelphia
Museum of Art, which has needed additional space for decades and which
received its last significant facelift ten years ago. Because of the space
crunch, the Art Museum has become increasingly cautious in considering
acquisitions and donations of art, in some cases passing up opportunities to
strengthen its collections.

Deaccessing - or selling off - works of art has taken on new importance
because of the museum’s space problems. And increasingly, curators have
been forced to juggle gallery space, rotating one masterpiece into public
view while another is sent to storage.

Despite the clear need for additional gallery and storage space, however,"
the museum has no plan, no plan to break out of its envelope in the next
fifteen years," according to Philadelphia Museum of Art’s president.

13 Skyscrapers and Environment

In the late 1960’s, many people in North America turned their attention to
environmental problems, and new steel-and-glass skyscrapers were widely
criticized. Ecologists pointed out that a cluster of tall buildings in a
city often overburdens public transportation and parking lot capacities.

Skyscrapers are also lavish consumers, and wasters, of electric power. In
one recent year, the addition of 17 million square feet of skyscraper office
space in New York City raised the peak daily demand for electricity by 120,
000 kilowatts-enough to supply the entire city of Albany, New York, for a
day.

Glass-walled skyscrapers can be especially wasteful. The heat loss (or
gain)through a wall of half-inch plate glass is more than ten times that
through a typical masonry wall filled with insulation board. To lessen the
strain on heating and air-conditioning equipment, builders of skyscrapers
have begun to use double-glazed panels of glass, and reflective glasses
coated with silver or gold mirror films that reduce glare as well as heat
gain. However, mirror-walled skyscrapers raise the temperature of the
surrounding air and affect neighboring buildings.

Skyscrapers put a severe strain on a city’s sanitation facilities, too. If
fully occupied, the two World Trade Center towers in New York City would
alone generate 2.25 million gallons of raw sewage each year-as much as a
city the size of Stanford, Connecticut , which has a population of more than
109, 000.

14 A Rare Fossil Record

The preservation of embryos and juveniles is a rate occurrence in the fossil
record. The tiny, delicate skeletons are usually scattered by scavengers or
destroyed by weathering before they can be fossilized. Ichthyosaurs had a
higher chance of being preserved than did terrestrial creatures because, as
marine animals, they tended to live in environments less subject to erosion.
Still, their fossilization required a suite of factors: a slow rate of decay
of soft tissues, little scavenging by other animals, a lack of swift
currents and waves to jumble and carry away small bones, and fairly rapid
burial. Given these factors, some areas have become a treasury of
well-preserved ichthyosaur fossils.

The deposits at Holzmaden, Germany, present an interesting case for
analysis. The ichthyosaur remains are found in black, bituminous marine
shales deposited about 190 million years ago. Over the years, thousands of
specimens of marine reptiles, fish and invertebrates have been recovered
from these rocks. The quality of preservation is outstanding, but what is
even more impressive is the number of ichthyosaur fossils containing
preserved embryos. Ichthyosaurs with embryos have been reported from 6
different levels of the shale in a small area around Holzmaden, suggesting
that a specific site was used by large numbers of ichthyosaurs repeatedly
over time. The embryos are quite advanced in their physical development;
their paddles, for example, are already well formed. One specimen is even
preserved in the birth canal. In addition, the shale contains the remains of
many newborns that are between 20 and 30 inches long.

Why are there so many pregnant females and young at Holzmaden when they are
so rare elsewhere? The quality of preservation is almost unmatched and
quarry operations have been carried out carefully with an awareness of the
value of the fossils. But these factors do not account for the interesting
question of how there came to be such a concentration of pregnant
ichthyosaurs in a particular place very close to their time of giving birth.

15 The Nobel Academy

For the last 82years, Sweden’s Nobel Academy has decided who will receive
the Nobel Prize in Literature, thereby determining who will be elevated from
the great and the near great to the immortal. But today the Academy is
coming under heavy criticism both from the without and from within. Critics
contend that the selection of the winners often has less to do with true
writing ability than with the peculiar internal politics of the Academy and
of Sweden itself. According to Ingmar Bjorksten, the cultural editor for one
of the country’s two major newspapers, the prize continues to represent
"what people call a very Swedish exercise: reflecting Swedish tastes."

The Academy has defended itself against such charges of provincialism in its
selection by asserting that its physical distance from the great literary
capitals of the world actually serves to protect the Academy from outside
influences. This may well be true, but critics respond that this very
distance may also be responsible for the Academy’s inability to perceive
accurately authentic trends in the literary world.

Regardless of concerns over the selection process, however, it seems that
the prize will continue to survive both as an indicator of the literature
that we most highly praise, and as an elusive goal that writers seek. If for
no other reason, the prize will continue to be desirable for the financial
rewards that accompany it; not only is the cash prize itself considerable,
but it also dramatically increases sales of an author’s books.

16. the war between Britain and France

In the late eighteenth century, battles raged in almost every corner of
Europe, as well as in the Middle East, South Africa, the West Indies, and
Latin America. In reality, however, there was only one major war during this
time, the war between Britain and France. All other battles were ancillary
to this larger conflict, and were often at least partially related to its
antagonist’ goals and strategies. France sought total domination of Europe.
This goal was obstructed by British independence and Britain’s efforts
throughout the continent to thwart Napoleon; through treaties. Britain built
coalitions (not dissimilar in concept to today’s NATO) guaranteeing British
participation in all major European conflicts. These two antagonists were
poorly matched, insofar as they had very unequal strengths; France was
predominant on land, Britain at sea. The French knew that, short of
defeating the British navy, their only hope of victory was to close all the
ports of Europe to British ships. Accordingly, France set out to overcome
Britain by extending its military domination from Moscow t Lisbon, from
Jutland to Caldaria. All of this entailed tremendous risk, because France
did not have the military resources to control this much territory and still
protect itself and maintain order at home.

French strategists calculated that a navy of 150 ships would provide the
force necessary to defeat the British navy. Such a force would give France a
three-to-two advantage over Britain. This advantage was deemed necessary
because of Britain’s superior sea skills and technology because of Britain
’s superior sea skills and technology, and also because Britain would be
fighting a defensive war, allowing it to win with fewer forces. Napoleon
never lost substantial impediment to his control of Europe. As his force
neared that goal, Napoleon grew increasingly impatient and began planning an
immediate attack.

17 Evolution of sleep

Sleep is very ancient. In the electroencephalographic sense we share it with
all the primates and almost all the other mammals and birds: it may extend
back as far as the reptiles.

There is some evidence that the two types of sleep, dreaming and dreamless,
depend on the life-style of the animal, and that predators are statistically
much more likely to dream than prey, which are in turn much more likely to
experience dreamless sleep. In dream sleep, the animal is powerfully
immobilized and remarkably unresponsive to external stimuli. Dreamless sleep
is much shallower, and we have all witnessed cats or dogs cocking their ears
to a sound when apparently fast asleep. The fact that deep dream sleep is
rare among pray today seems clearly to be a product of natural selection,
and it makes sense that today, when sleep is highly evolved, the stupid
animals are less frequently immobilized by deep sleep than the smart ones.
But why should they sleep deeply at all? Why should a state of such deep
immobilization ever have evolved?

Perhaps one useful hint about the original function of sleep is to be found
in the fact that dolphins and whales and aquatic mammals in genera seem to
sleep very little. There is, by and large, no place to hide in the ocean.
Could it be that, rather than increasing an animal’s vulnerability, the
University of Florida and Ray Middies of London University have suggested
this to be the case. It is conceivable that animals who are too stupid to be
quite on their own initiative are, during periods of high risk, immobilized
by the implacable arm of sleep. The point seems particularly clear for the
young of predatory animals. This is an interesting notion and probably at
least partly true.

18 Modern American Universities

Before the 1850’s, the United States had a number of small colleges, most
of them dating from colonial days. They were small, church connected
institutions whose primary concern was to shape the moral character of their
students.

Throughout Europe, institutions of higher learning had developed, bearing
the ancient name of university. In German university was concerned primarily
with creating and spreading knowledge, not morals. Between mid-century and
the end of the 1800’s, more than nine thousand young Americans,
dissatisfied with their training at home, went to Germany for advanced
study. Some of them return to become presidents of venerable
colleges-----Harvard, Yale, Columbia---and transform them into modern
universities. The new presidents broke all ties with the churches and
brought in a new kind of faculty. Professors were hired for their knowledge
of a subject, not because they were of the proper faith and had a strong arm
for disciplining students. The new principle was that a university was to
create knowledge as well as pass it on, and this called for a faculty
composed of teacher-scholars. Drilling and learning by rote were replaced by
the German method of lecturing, in which the professor’s own research was
presented in class. Graduate training leading to the Ph.D., an ancient
German degree signifying the highest level of advanced scholarly attainment,
was introduced. With the establishment of the seminar system, graduate
student learned to question, analyze, and conduct their own research.

At the same time, the new university greatly expanded in size and course
offerings, breaking completely out of the old, constricted curriculum of
mathematics, classics, rhetoric, and music. The president of Harvard
pioneered the elective system, by which students were able to choose their
own course of study. The notion of major fields of study emerged. The new
goal was to make the university relevant to the real pursuits of the world.
Paying close heed to the practical needs of society, the new universities
trained men and women to work at its tasks, with engineering students being
the most characteristic of the new regime. Students were also trained as
economists, architects, agriculturalists, social welfare workers, and
teachers.

19 children’s numerical skills

People appear to born to compute. The numerical skills of children develop
so early and so inexorably that it is easy to imagine an internal clock of
mathematical maturity guiding their growth. Not long after learning to walk
and talk, they can set the table with impress accuracy---one knife, one
spoon, one fork, for each of the five chairs.
Soon they are capable of nothing that they have placed five knives, spoons
and forks on the table and, a bit later, that this amounts to fifteen pieces
of silverware. Having thus mastered addition, they move on to subtraction.
It seems almost reasonable to expect that if a child were secluded on a
desert island at birth and retrieved seven years later, he or she could
enter a second enter a second-grade mathematics class without any serious
problems of intellectual adjustment.

Of course, the truth is not so simple. This century, the work of cognitive
psychologists has illuminated the subtle forms of daily learning on which
intellectual progress depends. Children were observed as they slowly
grasped-----or, as the case might be, bumped into----- concepts that adults
take for quantity is unchanged as water pours from a short glass into a tall
thin one. Psychologists have since demonstrated that young children, asked
to count the pencils in a pile, readily report the number of blue or red
pencils, but must be coaxed into finding the total. Such studies have
suggested that the rudiments of mathematics are mastered gradually, and with
effort. They have also suggested that the very concept of abstract
numbers------the idea of a oneness, a twoness, a threeness that applies to
any class of objects and is a prerequisite for doing anything more
mathematically demanding than setting a table-----is itself far from innate

20 The Historical Significance of American Revolution

The ways of history are so intricate and the motivations of human actions so
complex that it is always hazardous to attempt to represent events covering
a number of years, a multiplicity of persons, and distant localities as the
expression of one intellectual or social movement; yet the historical
process which culminated in the ascent of Thomas Jefferson to the presidency
can be regarded as the outstanding example not only of the birth of a new
way of life but of nationalism as a new way of life. The American Revolution
represents the link between the seventeenth century, in which modern England
became conscious of itself, and the awakening of modern Europe at the end of
the eighteenth century. It may seem strange that the march of history should
have had to cross the Atlantic Ocean, but only in the North American
colonies could a struggle for civic liberty lead also to the foundation of a
new nation. Here, in the popular rising against a “tyrannical” government,
the fruits were more than the securing of a freer constitution. They
included the growth of a nation born in liberty by the will of the people,
not from the roots of common descent, a geographic entity, or the ambitions
of king or dynasty. With the American nation, for the first time, a nation
was born, not in the dim past of history but before the eyes of the whole
world.

21 The Origin of Sports

When did sport begin? If sport is, in essence, play, the claim might be made
that sport is much older than humankind, for , as we all have observed, the
beasts play. Dogs and cats wrestle and play ball games. Fishes and birds
dance. The apes have simple, pleasurable games. Frolicking infants, school
children playing tag, and adult arm wrestlers are demonstrating strong,
transgenerational and transspecies bonds with the universe of animals -
past, present, and future. Young animals, particularly, tumble, chase, run
wrestle, mock, imitate, and laugh (or so it seems) to the point of delighted
exhaustion. Their play, and ours, appears to serve no other purpose than to
give pleasure to the players, and apparently, to remove us temporarily from
the anguish of life in earnest.

Some philosophers have claimed that our playfulness is the most noble part
of our basic nature. In their generous conceptions, play harmlessly and
experimentally permits us to put our creative forces, fantasy, and
imagination into action. Play is release from the tedious battles against
scarcity and decline which are the incessant, and inevitable, tragedies of
life. This is a grand conception that excites and provokes. The holders of
this view claim that the origins of our highest accomplishments ----
liturgy, literature, and law ---- can be traced to a play impulse which,
paradoxically, we see most purely enjoyed by young beasts and children. Our
sports, in this rather happy, nonfatalistic view of human nature, are more
splendid creations of the nondatable, transspecies play impulse.

22. Collectibles

Collectibles have been a part of almost every culture since ancient times.
Whereas some objects have been collected for their usefulness, others have
been selected for their aesthetic beauty alone. In the United States, the
kinds of collectibles currently popular range from traditional objects such
as stamps, coins, rare books, and art to more recent items of interest like
dolls, bottles, baseball cards, and comic books.

Interest in collectibles has increased enormously during the past decade, in
part because some collectibles have demonstrated their value as investments.
Especially during cycles of high inflation, investors try to purchase
tangibles that will at least retain their current market values. In general,
the most traditional collectibles will be sought because they have preserved
their value over the years, there is an organized auction market for them,
and they are most easily sold in the event that cash is needed. Some
examples of the most stable collectibles are old masters, Chinese ceramics,
stamps, coins, rare books, antique jewelry, silver, porcelain, art by
well-known artists, autographs, and period furniture. Other items of more
recent interest include old photograph records, old magazines, post cards,
baseball cards, art glass, dolls, classic cars, old bottles, and comic
books. These relatively new kinds of collectibles may actually appreciate
faster as short-term investments, but may not hold their value as long-term
investments. Once a collectible has had its initial play, it appreciates at
a fairly steady rate, supported by an increasing number of enthusiastic
collectors competing for the limited supply of collectibles that become
increasingly more difficult to locate.

23 Ford

Although Henry Ford’s name is closely associated with the concept of mass
production, he should receive equal credit for introducing labor practices
as early as 1913 that would be considered advanced even by today’s
standards. Safety measures were improved, and the work day was reduced to
eight hours, compared with the ten-or twelve-hour day common at the time. In
order to accommodate the shorter work day, the entire factory was converted
from two to three shifts.

In addition, sick leaves as well as improved medical care for those injured
on the job were instituted. The Ford Motor Company was one of the first
factories to develop a technical school to train specialized skilled
laborers and an English language school for immigrants. Some efforts were
even made to hire the handicapped and provide jobs for former convicts.

The most widely acclaimed innovation was the five-dollar-a-day minimum wage
that was offered in order to recruit and retain the best mechanics and to
discourage the growth of labor unions. Ford explained the new wage policy in
terms of efficiency and profit sharing. He also mentioned the fact that his
employees would be able to purchase the automobiles that they produced - in
effect creating a market for the product. In order to qualify for the
minimum wage, an employee had to establish a decent home and demonstrate
good personal habits, including sobriety, thriftiness, industriousness, and
dependability. Although some criticism was directed at Ford for involving
himself too much in the personal lives of his employees, there can be no
doubt that, at a time when immigrants were being taken advantage of in
frightful ways, Henry Ford was helping many people to establish themselves
in America.

24 Piano

The ancestry of the piano can be traced to the early keyboard instruments of
the fifteenth and sixteenth centuries --- the spinet, the dulcimer, and the
virginal. In the seventeenth century the organ, the clavichord, and the
harpsichord became the chief instruments of the keyboard group, a supremacy
they maintained until the piano supplanted them at the end of the eighteenth
century. The clavichord’s tone was metallic and never powerful;
nevertheless, because of the variety of tone possible to it, many composers
found the clavichord a sympathetic instrument for intimate chamber music.
The harpsichord with its bright, vigorous tone was the favorite instrument
for supporting the bass of the small orchestra of the period and for concert
use, but the character of the tone could not be varied save by mechanical or
structural devices.

The piano was perfected in the early eighteenth century by a harpsichord
maker in Italy (though musicologists point out several previous instances of
the instrument). This instrument was called a piano e forte (sort and loud),
to indicate its dynamic versatility; its strings were struck by a recoiling
hammer with a felt-padded head. The wires were much heavier in the earlier
instruments. A series of mechanical improvements continuing well into the
nineteenth century, including the introduction of pedals to sustain tone or
to soften it, the perfection of a metal frame, and steel wire of the finest
quality, finally produced an instrument capable of myriad tonal effects from
the most delicate harmonies to an almost orchestral fullness of sound, from
a liquid, singing tone to a sharp, percussive brilliance.

25. Movie Music

Accustomed though we are to speaking of the films made before 1927 as
“silent”, the film has never been, in the full sense of the word, silent.
From the very beginning, music was regarded as an indispensable
accompaniment; when the Lumiere films were shown at the first public film
exhibition in the United States in February 1896, they were accompanied by
piano improvisations on popular tunes. At first, the music played bore no
special relationship to the films; an accompaniment of any kind was
sufficient. Within a very short time, however, the incongruity of playing
lively music to a solemn film became apparent, and film pianists began to
take some care in matching their pieces to the mood of the film.

As movie theaters grew in number and importance, a violinist, and perhaps a
cellist, would be added to the pianist in certain cases, and in the larger
movie theaters small orchestras were formed. For a number of years the
selection of music for each film program rested entirely in the hands of the
conductor or leader of the orchestra, and very often the principal
qualification for holding such a position was not skill or taste so much as
the ownership of a large personal library of musical pieces. Since the
conductor seldom saw the films until the night before they were to be shown
(if indeed, the conductor was lucky enough to see them then), the musical
arrangement was normally improvised in the greatest hurry.

To help meet this difficulty, film distributing companies started the
practice of publishing suggestions for musical accompaniments. In 1909, for
example, the Edison Company began issuing with their films such indications
of mood as “pleasant”, “sad”, “lively”. The suggestions became more
explicit, and so emerged the musical cue sheet containing indications of
mood, the titles of suitable pieces of music, and precise directions to show
where one piece led into the next.

Certain films had music especially composed for them. The most famous of
these early special scores was that composed and arranged for D.W Griffith’
s film Birth of a Nation, which was released in 1915.

26. International Business and Cross-cultural Communication
The increase in international business and in foreign investment has created
a need for executives with knowledge of foreign languages and skills in
cross-cultural communication. Americans, however, have not been well trained
in either area and, consequently, have not enjoyed the same level of success
in negotiation in an international arena as have their foreign counterparts.

Negotiating is the process of communicating back and forth for the purpose
of reaching an agreement. It involves persuasion and compromise, but in
order to participate in either one, the negotiators must understand the ways
in which people are persuaded and how compromise is reached within the
culture of the negotiation.

In many international business negotiations abroad, Americans are perceived
as wealthy and impersonal. It often appears to the foreign negotiator that
the American represents a large multi-million-dollar corporation that can
afford to pay the price without bargaining further. The American negotiator
’s role becomes that of an impersonal purveyor of information and cash.

In studies of American negotiators abroad, several traits have been
identified that may serve to confirm this stereotypical perception, while
undermining the negotiator’s position. Two traits in particular that cause
cross-cultural misunderstanding are directness and impatience on the part of
the American negotiator. Furthermore, American negotiators often insist on
realizing short-term goals. Foreign negotiators, on the other hand, may
value the relationship established between negotiators and may be willing to
invest time in it for long- term benefits. In order to solidify the
relationship, they may opt for indirect interactions without regard for the
time involved in getting to know the other negotiator.

27. Scientific Theories

In science, a theory is a reasonable explanation of observed events that are
related. A theory often involves an imaginary model that helps scientists
picture the way an observed event could be produced. A good example of this
is found in the kinetic molecular theory, in which gases are pictured as
being made up of many small particles that are in constant motion.

A useful theory, in addition to explaining past observations, helps to
predict events that have not as yet been observed. After a theory has been
publicized, scientists design experiments to test the theory. If
observations confirm the scientist’s predictions, the theory is supported.
If observations do not confirm the predictions, the scientists must search
further. There may be a fault in the experiment, or the theory may have to
be revised or rejected.

Science involves imagination and creative thinking as well as collecting
information and performing experiments. Facts by themselves are not science.
As the mathematician Jules Henri Poincare said, “Science is built with
facts just as a house is built with bricks, but a collection of facts cannot
be called science any more than a pile of bricks can be called a house.”

Most scientists start an investigation by finding out what other scientists
have learned about a particular problem. After known facts have been
gathered, the scientist comes to the part of the investigation that requires
considerable imagination. Possible solutions to the problem are formulated.
These possible solutions are called hypotheses.

In a way, any hypothesis is a leap into the unknown. It extends the
scientist’s thinking beyond the known facts. The scientist plans
experiments, performs calculations, and makes observations to test
hypotheses. Without hypothesis, further investigation lacks purpose and
direction. When hypotheses are confirmed, they are incorporated into
theories.

28 Changing Roles of Public Education

One of the most important social developments that helped to make possible a
shift in thinking about the role of public education was the effect of the
baby boom of the 1950’s and 1960’s on the schools. In the 1920’s, but
especially in the Depression conditions of the 1930’s, the United States
experienced a declining birth rate --- every thousand women aged fifteen to
forty-four gave birth to about 118 live children in 1920, 89.2 in 1930, 75.8
in 1936, and 80 in 1940. With the growing prosperity brought on by the
Second World War and the economic boom that followed it young people married
and established households earlier and began to raise larger families than
had their predecessors during the Depression. Birth rates rose to 102 per
thousand in 1946,106.2 in 1950, and 118 in 1955. Although economics was
probably the most important determinant, it is not the only explanation for
the baby boom. The increased value placed on the idea of the family also
helps to explain this rise in birth rates. The baby boomers began streaming
into the first grade by the mid 1940’s and became a flood by 1950. The
public school system suddenly found itself overtaxed. While the number of
schoolchildren rose because of wartime and postwar conditions, these same
conditions made the schools even less prepared to cope with the
food. The wartime economy meant that few new schools were built between 1940
and 1945. Moreover, during the war and in the boom times that followed,
large numbers of teachers left their profession for better- paying jobs
elsewhere in the economy.

Therefore in the 1950’s and 1960’s, the baby boom hit an antiquated and
inadequate school system. Consequently, the “ custodial rhetoric” of the
1930’s and early 1940’s no longer made sense that is, keeping youths aged
sixteen and older out of the labor market by keeping them in school could no
longer be a high priority for an institution unable to find space and staff
to teach younger children aged five to sixteen. With the baby boom, the
focus of educators and of laymen interested in education inevitably turned
toward the lower grades and back to basic academic skills and discipline.
The system no longer had much interest in offering nontraditional, new, and
extra services to older youths.

29 Telecommuting

Telecommuting-- substituting the computer for the trip to the job ---- has
been hailed as a solution to all kinds of problems related to office work.

For workers it promises freedom from the office, less time wasted in
traffic, and help with child-care conflicts. For management, telecommuting
helps keep high performers on board, minimizes tardiness and absenteeism by
eliminating commutes, allows periods of solitude for high-concentration
tasks, and provides scheduling flexibility. In some areas, such as Southern
California and Seattle, Washington, local governments are encouraging
companies to start telecommuting programs in order to reduce rush-hour
congestion and improve air quality.

But these benefits do not come easily. Making a telecommuting program work
requires careful planning and an understanding of the differences between
telecommuting realities and popular images.

Many workers are seduced by rosy illusions of life as a telecommuter. A
computer programmer from New York City moves to the tranquil Adirondack
Mountains and stays in contact with her office via computer. A manager comes
in to his office three days a week and works at home the other two. An
accountant stays home to care for her sick child; she hooks up her telephone
modern connections and does office work between calls to the doctor.

These are powerful images, but they are a limited reflection of reality.
Telecommuting workers soon learn that it is almost impossible to concentrate
on work and care for a young child at the same time. Before a certain age,
young children cannot recognize, much less respect, the necessary boundaries
between work and family. Additional child support is necessary if the parent
is to get any work done.

Management too must separate the myth from the reality. Although the media
has paid a great deal of attention to telecommuting in most cases it is the
employee’s situation, not the availability of technology that precipitates
a telecommuting arrangement.

That is partly why, despite the widespread press coverage, the number of
companies with work-at-home programs or policy guidelines remains small.

30 The origin of Refrigerators

By the mid-nineteenth century, the term “icebox” had entered the American
language, but ice was still only beginning to affect the diet of ordinary
citizens in the United States. The ice trade grew with the growth of cities.
Ice was used in hotels, taverns, and hospitals, and by some forward-looking
city dealers in fresh meat, fresh fish, and butter. After the Civil War
(1861-1865), as ice was used to refrigerate freight cars, it also came into
household use. Even before 1880, half of the ice sold in New York,
Philadelphia, and Baltimore, and one-third of that sold in Boston and
Chicago, went to families for their own use. This had become possible
because a new household convenience, the icebox, a precursor of the modern
refrigerator, had been invented.

Making an efficient icebox was not as easy as we might now suppose. In the
early nineteenth century, the knowledge of the physics of heat, which was
essential to a science of refrigeration, was rudimentary. The commonsense
notion that the best icebox was one that prevented the ice from melting was
of course mistaken, for it was the melting of the ice that performed the
cooling. Nevertheless, early efforts to economize ice included wrapping up
the ice in blankets, which kept the ice from doing its job. Not until near
the end of the nineteenth century did inventors achieve the delicate balance
of insulation and circulation needed for an efficient icebox.

But as early as 1803, and ingenious Maryland farmer, Thomas Moore, had been
on the right track. He owned a farm about twenty miles outside the city of
Washington, for which the village of Georgetown was the market center. When
he used an icebox of his own design to transport his butter to market, he
found that customers would pass up the rapidly melting stuff in the tubs of
his competitors to pay a premium price for his butter, still fresh and hard
in neat, one-pound bricks. One advantage of his icebox, Moore explained, was
that farmers would no longer have to travel to market at night in order to
keep their produce cool.

31 British Columbia

British Columbia is the third largest Canadian provinces, both in area and
population. It is nearly 1.5 times as large as Texas, and extends 800 miles
(1,280km) north from the United States border. It includes Canada’s entire
west coast and the islands just off the coast.

Most of British Columbia is mountainous, with long rugged ranges running
north and south. Even the coastal islands are the remains of a mountain
range that existed thousands of years ago. During the last Ice Age, this
range was scoured by glaciers until most of it was beneath the sea. Its
peaks now show as islands scattered along the coast.

The southwestern coastal region has a humid mild marine climate. Sea winds
that blow inland from the west are warmed by a current of warm water that
flows through the Pacific Ocean. As a result, winter temperatures average
above freezing and summers are mild. These warm western winds also carry
moisture from the ocean.

Inland from the coast, the winds from the Pacific meet the mountain barriers
of the coastal ranges and the Rocky Mountains. As they rise to cross the
mountains, the winds are cooled, and their moisture begins to fall as rain.
On some of the western slopes almost 200 inches (500cm) of rain fall each
year.

More than half of British Columbia is heavily forested. On mountain slopes
that receive plentiful rainfall, huge Douglas firs rise in towering columns.
These forest giants often grow to be as much as 300 feet (90m) tall, with
diameters up to 10 feet (3m). More lumber is produced from these trees than
from any other kind of tree in North America. Hemlock, red cedar, and balsam
fir are among the other trees found in British Columbia.

32 Botany

Botany, the study of plants, occupies a peculiar position in the history of
human knowledge. For many thousands of years it was the one field of
awareness about which humans had anything more than the vaguest of insights.
It is impossible to know today just what our Stone Age ancestors knew about
plants, but form what we can observe of pre- industrial societies that still
exist a detailed learning of plants and their properties must be extremely
ancient. This is logical. Plants are the basis of the food pyramid for all
living things even for other plants. They have always been enormously
important to the welfare of people not only for food, but also for clothing,
weapons, tools, dyes, medicines, shelter, and a great many other purposes.
Tribes living today in the jungles of the Amazon recognize literally
hundreds of plants and know many properties of each. To them, botany, as
such, has no name and is probably not even recognized as a special branch of
“knowledge” at all.

Unfortunately, the more industrialized we become the farther away we move
from direct contact with plants, and the less distinct our knowledge of
botany grows. Yet everyone comes unconsciously on an amazing amount of
botanical knowledge, and few people will fail to recognize a rose, an apple,
or an orchid. When our Neolithic ancestors, living in the Middle East about
10,000 years ago, discovered that certain grasses could be harvested and
their seeds planted for richer yields the next season the first great step
in a new association of plants and humans was taken. Grains were discovered
and from them flowed the marvel of agriculture: cultivated crops. From then
on, humans would increasingly take their living from the controlled
production of a few plants, rather than getting a little here and a little
there from many varieties that grew wild- and the accumulated knowledge of
tens of thousands of years of experience and intimacy with plants in the
wild would begin to fade away.

33 Plankton

Scattered through the seas of the world are billions of tons of small plants
and animals called plankton. Most of these plants and animals are too small
for the human eye to see. They drift about lazily with the currents,
providing a basic food for many larger animals.

Plankton has been described as the equivalent of the grasses that grow on
the dry land continents, and the comparison is an appropriate one. In
potential food value, however, plankton far outweighs that of the land
grasses. One scientist has estimated that while grasses of the world produce
about 49 billion tons of valuable carbohydrates each year, the sea’s
plankton generates more than twice as much.

Despite its enormous food potential, little effect was made until recently
to farm plankton as we farm grasses on land. Now marine scientists have at
last begun to study this possibility, especially as the sea’s resources
loom even more important as a means of feeding an expanding world
population.

No one yet has seriously suggested that “plankton-burgers” may soon become
popular around the world. As a possible farmed supplementary food source,
however, plankton is gaining considerable interest among marine scientists.

One type of plankton that seems to have great harvest possibilities is a
tiny shrimp-like creature called krill. Growing to two or three inches long,
krill provides the major food for the great blue whale, the largest animal
to ever inhabit the Earth. Realizing that this whale may grow to 100 feet
and weigh 150 tons at maturity, it is not surprising that each one

34 Raising Oysters

In the oysters were raised in much the same way as dirt farmers raised
tomatoes- by transplanting them. First, farmers selected the oyster bed,
cleared the bottom of old shells and other debris, then scattered clean
shells about. Next, they ”planted” fertilized oyster eggs, which within
two or three weeks hatched into larvae. The larvae drifted until they
attached themselves to the clean shells on the bottom. There they remained
and in time grew into baby oysters called seed or spat. The spat grew larger
by drawing in seawater from which they derived microscopic particles of
food. Before long, farmers gathered the baby oysters, transplanted them once
more into another body of water to fatten them up.

Until recently the supply of wild oysters and those crudely farmed were more
than enough to satisfy people’s needs. But today the delectable seafood is
no longer available in abundance. The problem has become so serious that
some oyster beds have vanished entirely.

Fortunately, as far back as the early 1900’s marine biologists realized
that if new measures were not taken, oysters would become extinct or at best
a luxury food. So they set up well-equipped hatcheries and went to work. But
they did not have the proper equipment or the skill to handle the eggs. They
did not know when, what, and how to feed the larvae. And they knew little
about the predators that attack and eat baby oysters by the millions. They
failed, but they doggedly kept at it. Finally, in the 1940’s a significant
breakthrough was made.

The marine biologists discovered that by raising the temperature of the
water, they could induce oysters to spawn not only in the summer but also in
the fall, winter, and spring. Later they developed a technique for feeding
the larvae and rearing them to spat. Going still further, they succeeded in
breeding new strains that were resistant to diseases, grew faster and
larger, and flourished in water of different salinities and temperatures. In
addition, the cultivated oysters tasted better!

35 Oil Refining

An important new industry, oil refining, grew after the Civil war. Crude
oil, or petroleum - a dark, thick ooze from the earth - had been known for
hundreds of years, but little use had ever been made of it. In the 1850’s
Samuel M. Kier, a manufacturer in western Pennsylvania, began collecting the
oil from local seepages and refining it into kerosene. Refining, like
smelting, is a process of removing impurities from a raw material.

Kerosene was used to light lamps. It was a cheap substitute for whale oil,
which was becoming harder to get. Soon there was a large demand for
kerosene. People began to search for new supplies of petroleum.

The first oil well was drilled by E.L. Drake, a retired railroad conductor.
In 1859 he began drilling in Titusville, Pennsylvania. The whole venture
seemed so impractical and foolish that onlookers called it “Drake’s
Folly”. But when he had drilled down about 70 feet (21 meters), Drake
struck oil. His well began to yield 20 barrels of crude oil a day.

News of Drake’s success brought oil prospectors to the scene. By the early
1860’s these wildcatters were drilling for “black gold” all over western
Pennsylvania. The boom rivaled the California gold rush of 1848 in its
excitement and Wild West atmosphere. And it brought far more wealth to the
prospectors than any gold rush.

Crude oil could be refined into many products. For some years kerosene
continued to be the principal one. It was sold in grocery stores and
door-to-door. In the 1880’s refiners learned how to make other petroleum
products such as waxes and lubricating oils. Petroleum was not then used to
make gasoline or heating oil.

36 Plate Tectonics and Sea-floor Spreading

The theory of plate tectonics describes the motions of the lithosphere, the
comparatively rigid outer layer of the Earth that includes all the crust and
part of the underlying mantle. The lithosphere is divided into a few dozen
plates of various sizes and shapes, in general the plates are in motion with
respect to one another. A mid-ocean ridge is a boundary between plates where
new lithospheric material is injected from below. As the plates diverge from
a mid-ocean ridge they slide on a more yielding layer at the base of the
lithosphere.

Since the size of the Earth is essentially constant, new lithosphere can be
created at the mid-ocean ridges only if an equal amount of lithospheric
material is consumed elsewhere. The site of this destruction is another kind
of plate boundary: a seduction zone. There one plate dives under the edge of
another and is reincorporated into the mantle. Both kinds of plate boundary
are associated with fault systems, earthquakes and volcanism, but the kinds
of geologic activity observed at the two boundaries are quite different.

The idea of sea-floor spreading actually preceded the theory of plate
tectonics. In its original version, in the early 1960’s, it described the
creation and destruction of the ocean floor, but it did not specify rigid
lithospheric plates. The hypothesis was substantiated soon afterward by the
discovery that periodic reversals of the Earth’s magnetic field are
recorded in the oceanic crust. As magma rises under the mid-ocean ridge,
ferromagnetic minerals in the magma become magnetized in the direction of
the magma become magnetized in the direction of the geomagnetic field. When
the magma cools and solidifies, the direction and the polarity of the field
are preserved in the magnetized volcanic rock. Reversals of the field give
rise to a series of magnetic stripes running parallel to the axis of the
rift. The oceanic crust thus serves as a magnetic tape recording of the
history of the geomagnetic field that can be dated independently; the width
of the stripes indicates the rate of the sea-floor spreading.

37 Icebergs

Icebergs are among nature’s most spectacular creations, and yet most people
have never seen one. A vague air of mystery envelops them. They come into
being ----- somewhere ------in faraway, frigid waters, amid thunderous noise
and splashing turbulence, which in most cases no one hears or sees. They
exist only a short time and then slowly waste away just as unnoticed.

Objects of sheerest beauty they have been called. Appearing in an endless
variety of shapes, they may be dazzlingly white, or they may be glassy blue,
green or purple, tinted faintly of in darker hues. They are graceful,
stately, inspiring ----- in calm, sunlight seas.

But they are also called frightening and dangerous, and that they are ----
in the night, in the fog, and in storms. Even in clear weather one is wise
to stay a safe distance away from them. Most of their bulk is hidden below
the water, so their underwater parts may extend out far beyond the visible
top. Also, they may roll over unexpectedly, churning the waters around them.

Icebergs are parts of glaciers that break off, drift into the water, float
about awhile, and finally melt. Icebergs afloat today are made of snowflakes
that have fallen over long ages of time. They embody snows that drifted down
hundreds, or many thousands, or in some cases maybe a million years ago. The
snows fell in polar regions and on cold mountains, where they melted only a
little or not at all, and so collected to great depths over the years and
centuries.

As each year’s snow accumulation lay on the surface, evaporation and
melting caused the snowflakes slowly to lose their feathery points and
become tiny grains of ice. When new snow fell on top of the old, it too
turned to icy grains. So blankets of snow and ice grains mounted layer upon
layer and were of such great thickness that the weight of the upper layers
compressed the lower ones. With time and pressure from above, the many small
ice grains joined and changed to larger crystals, and eventually the deeper
crystals merged into a solid mass of ice.

38 Topaz

Topaz is a hard, transparent mineral. It is a compound of aluminum, silica,
and fluorine. Gem topaz is valuable. Jewelers call this variety of the stone
“precious topaz”. The best-known precious topaz gems range in color from
rich yellow to light brown or pinkish red. Topaz is one of the hardest gem
minerals. In the mineral table of hardness, it has a rating of 8, which
means that a knife cannot cut it, and that topaz will scratch quartz.

The golden variety of precious topaz is quite uncommon. Most of the world’s
topaz is white or blue. The white and blue crystals of topaz are large,
often weighing thousands of carats. For this reason, the value of topaz does
not depend so much on its size as it does with diamonds and many other
precious stones, where the value increases about four times with each
doubling of weight. The value of a topaz is largely determined by its
quality. But color is also important: blue topaz, for instance, is often
irradiated to deepen and improve its color.

Blue topaz is often sold as aquamarine and a variety of brown quartz is
widely sold as topaz. The quartz is much less brilliant and more plentiful
than true topaz. Most of it is variety of amethyst: that heat has turned
brown.

39 The Salinity of Ocean Waters

If the salinity of ocean waters is analyzed, it is found to vary only
slightly from place to place. Nevertheless, some of these small changes are
important. There are three basic processes that cause a change in oceanic
salinity. One of these is the subtraction of water from the ocean by means
of evaporation--- conversion of liquid water to water vapor. In this manner
the salinity is increased, since the salts stay behind. If this is carried
to the extreme, of course, white crystals of salt would be left behind.

The opposite of evaporation is precipitation, such as rain, by which water
is added to the ocean. Here the ocean is being diluted so that the salinity
is decreased. This may occur in areas of high rainfall or in coastal regions
where rivers flow into the ocean. Thus salinity may be increased by the
subtraction of water by evaporation, or decreased by the addition of fresh
water by precipitation or runoff.

Normally, in tropical regions where the sun is very strong, the ocean
salinity is somewhat higher than it is in other parts of the world where
there is not as much evaporation. Similarly, in coastal regions where rivers
dilute the sea, salinity is somewhat lower than in other oceanic areas.

A third process by which salinity may be altered is associated with the
formation and melting of sea ice. When sea water is frozen, the dissolved
materials are left behind. In this manner, sea water directly materials are
left behind. In this manner, sea water directly beneath freshly formed sea
ice has a higher salinity than it did before the ice appeared. Of course,
when this ice melts, it will tend to decrease the salinity of the
surrounding water.

In the Weddell Sea Antarctica, the densest water in the oceans is formed as
a result of this freezing process, which increases the salinity of cold
water. This heavy water sinks and is found in the deeper portions of the
oceans of the world.

40 Cohesion-tension Theory

Atmospheric pressure can support a column of water up to 10 meters high. But
plants can move water much higher; the sequoia tree can pump water to its
very top more than 100 meters above the ground. Until the end of the
nineteenth century, the movement of water in trees and other tall plants was
a mystery. Some botanists hypothesized that the living cells of plants acted
as pumps. But many experiments demonstrated that the stems of plants in
which all the cells are killed can still move water to appreciable heights.
Other explanations for the movement of water in plants have been based on
root pressure, a push on the water from the roots at the bottom of the
plant. But root pressure is not nearly great enough to push water to the
tops of tall trees. Furthermore, the conifers, which are among the tallest
trees, have unusually low root pressures.

If water is not pumped to the top of a tall tree, and if it is not pushed to
the top of a tall tree, then we may ask: how does it get there? According to
the currently accepted cohesion-tension theory, water is pulled there. The
pull on a rising column of water in a plant results from the evaporation of
water at the top of the plant. As water is lost from the surface of the
leaves, a negative pressure, or tension, is created. The evaporated water is
replaced by water moving from inside the plant in unbroken columns that
extend from the top of a plant to its roots. The same forces that create
surface tension in any sample of water are responsible for the maintenance
of these unbroken columns of water. When water is confined in tubes of very
small bore, the forces of cohesion (the attraction between water molecules)
are so great that the strength of a column of water compares with the
strength of a steel wire of the same diameter. This cohesive strength
permits columns of water to be pulled to great heights without being broken.

41 American black bears

American black bears appear in a variety of colors despite their name. In
the eastern part of their range, most of these brown, red, or even yellow
coats. To the north, the black bear is actually gray or white in color. Even
in the same litter, both brown and black furred bears may be born.

Black bears are the smallest of all American bears, ranging in length from
five to six feet, weighing from three hundred to five hundred pounds their
eyes and ears are small and their eyesight and hearing are not as good as
their sense of smell.

Like all bears, the black bear is timid, clumsy, and rarely dangerous, but
if attacked, most can climb trees and cover ground at great speeds. When
angry or frightened, it is a formidable enemy.

Black bears feed on leaves, herbs. Fruit, berries, insects, fish, and even
larger animals. One of the most interesting characteristics of bears,
including the black bear, is their winter sleep. Unlike squirrels,
woodchucks, and many other woodland animals, bears do not actually
hibernate. Although the bear does not during the winter moths, sustaining
itself from body fat, its temperature remains almost normal, and it breathes
regularly four or five times per minute.

Most black bears live alone, except during mating season. They prefer to
live in caves, hollow logs, or dense thickets. A little of one to four cubs
is born in January or February after a gestation period of six to nine
months, and they remain with their mother until they are fully grown or
about one and a half years old. Black bears can live as long as thirty years
in the wild, and even longer in game preserves set aside for them.

42 Coal-fired power plants

The invention of the incandescent light bulb by Thomas A. Edison in 1879
created a demand for a cheap, readily available fuel with which to generate
large amounts of electric power. Coal seemed to fit the bill, and it fueled
the earliest power stations. (which were set up at the end of the nineteenth
century by Edison himself). As more power plants were constructed throughout
the country, the reliance on coal increased throughout the country, the
reliance on coal increased. Since the First
World War, coal-fired power plants had a combined in the United States each
year. In 1986 such plants had a combined generating capacity of 289,000
megawatts and consumed 83 percent of the nearly 900 million tons of coal
mined in the country that year. Given the uncertainty in the future growth
of the nearly 900 million tons of coal mined in the country that year. Given
the uncertainty in the future growth of nuclear
power and in the supply of oil and natural gas, coal-fired power plants
could well provide up to 70 percent of the electric power in the United
States by the end of the century.

Yet, in spite of the fact that coal has long been a source of electricity
and may remain on for many years(coal represents about 80 percent of United
States fossil-fuel reserves), it has actually never been the most desirable
fossil fuel for power plants. Coal contains less energy per unit of weight
than weight than natural gas or oil; it is difficult to transport, and it is
associated with a host of environmental issues, among them acid rain. Since
the late 1960’s problems of emission control and waste disposal have
sharply reduced the appeal of coal-fired power plants. The cost of
ameliorating these environment problems along with the rising cost of
building a facility as large and complex as a coal-fired power plant, have
also made such plants less attractive from a purely economic perspective.

Changes in the technological base of coal-fired power plants could restore
their attractiveness, however. Whereas some of these changes are intended
mainly to increase the productivity of existing plants, completely new
technologies for burning coal cleanly are also being developed.

43 Statistics

There were two widely divergent influences on the early development of
statistical methods. Statistics had a mother who was dedicated to keeping
orderly records of government units (states and statistics come from the
same Latin root status) and a gentlemanly gambling father who relied on
mathematics to increase his skill at playing the odds in games of chance.
The influence of the mother on the offspring, statistics, is represented by
counting, measuring, describing, tabulating, ordering, and the taking of
censuses-all of which led to modern descriptive statistics. From the
influence of the father came modern inferential statistics, which is based
squarely on theories of probability.

Describing collections involves tabulating, depicting and describing
collections of data. These data may be quantitative such as measures of
height, intelligence or grade level------variables that are characterized by
an underlying continuum---or the data may represent qualitative variables,
such as sex, college major or personality type. Large masses of data must
generally undergo a process of summarization or reduction before they are
comprehensible. Descriptive statistics is a tool for describing or
summarizing or reducing to comprehensible form the properties of an
otherwise unwieldy mass of data.

Inferential statistics is a formalized body of methods for solving another
class of problems that present great of problems characteristically involves
attempts to make predictions using a sample of observations. For example, a
school superintendent wishes to determine the proportion of children in a
large school system who come to school without breakfast, have been
vaccinated for flu, or whatever. Having a little knowledge of statistics,
the superintendent would know that it is unnecessary and inefficient to
question each child: the proportion for the sample of as few as 100
children. Thus, the purpose of inferential statistics is to predict or
estimate characteristics of a population from a knowledge of the
characteristics of only a sample of the population.

44 Obtaining Fresh water from icebergs

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 has 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 on the oceans
every year are 7,659 trillion metric tons of ice encased in 10000 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 desalinization, or removing salt from water.

45 The source of Energy

A summary of the physical and chemical nature of life must begin, not on the
Earth, but in the Sun; in fact, at the Sun’s very center. It is here that
is to be found the source of the energy that the Sun constantly pours out
into space as light and heat. This energy is librated at the center of the
Sun as billions upon billions of nuclei of hydrogen atoms collide with each
other and fuse together to form nuclei of helium, and in doing so, release
some of the energy that is stored in the nuclei of atoms. The output of
light and heat of the Sun requires that some 600 million tons of hydrogen be
converted into helium in the Sun every second. This the Sun has been doing
for several thousands of millions of year.

The nuclear energy is released at the Sun’s center as high-energy gamma
radiation, a form of electromagnetic radiation like light and radio waves,
only of very much shorter wavelength. This gamma radiation is absorbed by
atoms inside the Sun to be reemitted at slightly longer wavelengths. This
radiation, in its turn is absorbed and reemitted. As the energy filters
through the layers of the solar interior, it passes through the X-ray part
of the spectrum eventually becoming light. At this stage, it has reached
what we call the solar surface, and can escape into space without being
absorbed further by solar atoms. A very small fraction of the Sun’s light
and heat is emitted in such directions that after passing unhindered through
interplanetary space, it hits the Earth.

46 Vision

Human vision like that of other primates has evolved in an arboreal
environment. In the dense complex world of a tropical forest, it is more
important to see well that to develop an acute sense of smell. In the course
of evolution members of the primate line have acquired large eyes while the
snout has shrunk to give the eye an unimpeded view. Of mammals only humans
and some primates enjoy color vision. The red flag is black to the bull.
Horses live in a monochrome world .light visible to human eyes however
occupies only a very narrow band in the whole electromagnetic spectrum.
Ultraviolet rays are invisible to humans though ants and honeybees are
sensitive to them. Humans though ants and honeybees are sensitive to them.
Humans have no direct perception of infrared rays unlike the rattlesnake
which has receptors tuned into wavelengths longer than 0.7 micron. The world
would look eerily different if human eyes were sensitive to infrared
radiation. Then instead of the darkness of night, we would be able to move
easily in a strange shadowless world where objects glowed with varying
degrees of intensity. But human eyes excel in other ways. They are in fact
remarkably discerning in color gradation. The color sensitivity of normal
human vision is rarely surpassed even by sophisticated technical devices.

47 Folk Cultures

A folk culture is a small isolated, cohesive, conservative, nearly self-
sufficient group that is homogeneous in custom and race with a strong family
or clan structure and highly developed rituals. Order is maintained through
sanctions based in the religion or family and interpersonal. Relationships
are strong. Tradition is paramount, and change comes infrequently and
slowly. There is relatively little division of labor into specialized
duties. Rather, each person is expected to perform a great variety of tasks,
though duties may differ between the sexes. Most goods are handmade and
subsistence economy prevails. Individualism is weakly developed in folk
cultures as are social classes. Unaltered folk cultures no longer exist in
industrialized countries such as the United States and Canada. Perhaps the
nearest modern equivalent in Anglo America is the Amish, a German American
farming sect that largely renounces the products and labor saving devices of
the industrial age. In Amish areas, horse drawn buggies still serve as a
local transportation device and the faithful are not permitted to own
automobiles. The Amish’s central religious concept of Demut “humility”,
clearly reflects the weakness of individualism and social class so typical
of folk cultures and there is a corresponding strength of Amish group
identity. Rarely do the Amish marry outside their sect. The religion, a
variety of the Mennonite faith, provides the principal mechanism for
maintaining order.

By contrast a popular culture is a large heterogeneous group often highly
individualistic and a pronounced many specialized professions. Secular
institutions of control such as the police and army take the place of
religion and family in maintaining order, and a money-based economy
prevails. Because of these contrasts, “popular” may be viewed as clearly
different from “folk”. The popular is replacing the folk in industrialized
countries and in many developing nations. Folk-made objects give way to
their popular equivalent, usually because the popular item is more quickly
or cheaply produced, is easier or time saving to use or leads more prestige
to the owner.

48 Bacteria b

Bacteria are extremely small living things. While we measure our own sizes
in inches or centimeters, bacterial size is measured in microns. One micron
is a thousandth of a millimeter: a pinhead is about a millimeter across.
Rod-shaped bacteria are usually from two to four microns long, while rounded
ones are generally one micron in diameter. Thus if you enlarged a rounded
bacterium a thousand times, it would be just about the size of a pinhead. An
adult human magnified by the same amount would be over a mile (1.6
kilometer) tall.

Even with an ordinary microscope, you must look closely to see bacteria.
Using a magnification of 100 times, one finds that bacteria are barely
visible as tiny rods or dots. One cannot make out anything of their
structure. Using special stains, one can see that some bacteria have
attached to them wavy-looking “hairs” called flagella. Others have only
one flagellum. The flagella rotate, pushing the bacteria through the water.
Many bacteria lack flagella and cannot move about by their own power, while
others can glide along over surfaces by some little- understood mechanism.

From the bacteria point of view, the world is a very different place from
what it is to humans. To a bacterium water is as thick as molasses is to us.
Bacteria are so small that they are influenced by the movements of the
chemical molecules around them. Bacteria under the microscope, even those
with no flagella, often bounce about in the water. This is because they
collide with the watery molecules and are pushed this way and that.
Molecules move so rapidly that within a tenth of a second the molecules
round a bacteria have all been replaced by new ones; even bacteria without
flagella are thus constantly exposed to a changing environment.

49 Sleep

Sleet is part of a person’s daily activity cycle. There are several
different stages of sleep, and they too occur in cycles. If you are an
average sleeper, your sleep cycle is as follows. When you fist drift off
into slumber, your eyes will roll about a bit, you temperature will drop
slightly, your muscles will relax, and your breathing well slow and become
quite regular. Your brain waves slow and become quite regular. Your brain
waves slow down a bit too, with the alpha rhythm of rather fast waves 1
sleep. For the next half hour or so, as you relax more and more, you will
drift down through stage 2 and stage 3 sleep. The lower your stage of sleep.
Slower your brain waves will be. Then about 40to 69 minutes after you lose
consciousness you will have reached the deepest sleep of all. Your brain
will show the large slow waves that are known as the delta rhythm. This is
stage 4 sleep.

You do not remain at this deep fourth stage all night long, but instead
about 80 minutes after you fall into slumber, your brain activity level will
increase again slightly. The delta rhythm will disappear, to be replaced by
the activity pattern of brain waves. Your eyes will begin to dart around
under your closed eyelids as if you were looking at something occurring in
front of you. This period of rapid eye movement lasts for some 8 to 15
minutes and is called REM sleep. It is during REM sleep period, your body
will soon relax again, your breathing will slip gently back from stage 1 to
stage 4 sleep----only to rise once again to the surface of near
consciousness some 80 minutes later.

50. Cells and Temperature

Cells cannot remain alive outside certain limits of temperature and much
narrower limits mark the boundaries of effective functioning. Enzyme systems
of mammals and birds are most efficient only within a narrow range around
37C;a departure of a few degrees from this value seriously impairs their
functioning. Even though cells can survive wider fluctuations the integrated
actions of bodily systems are impaired. Other animals have a wider tolerance
for changes of bodily temperature.

For centuries it has been recognized that mammals and birds differ from
other animals in the way they regulate body temperature. Ways of
characterizing the difference have become more accurate and meaningful over
time, but popular terminology still reflects the old division into
“warm-blooded” and “cold-blooded” species; warm-blooded included mammals
and birds whereas all other creatures were considered cold- blooded. As more
species were studied, it became evident that this classification was
inadequate. A fence lizard or a desert iguana-each cold-blooded----usually
has a body temperature only a degree or two below that of humans and so is
not cold. Therefore the next distinction was made between animals that
maintain a constant body temperature, called home0therms, and those whose
body temperature varies with their environments, called poikilotherms. But
this classification also proved inadequate, because among mammals there are
many that vary their body temperatures during hibernation. Furthermore, many
invertebrates that live in the depths of the ocean never experience change
in the depths of the ocean never experience change in the chill of the deep
water, and their body temperatures remain constant.


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