新概念英语第四册课文word版

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Lesson1

We can read of things that happened 5,000 years ago in the Near East, where people first learned to write. But there are some parts of the world where even now people cannot write. The only way that they can preserve their history is to recount it as sagas--legends

handed

down

from

one

generation of story-tellers to another. These legends are useful because they can tell us something about migrations of people who lived long ago, but none could write down what they did. Anthropologists wondered where the remote ancestors of the Polynesian peoples now living in the Pacific Islands came from. The sagas of these people explain that some of them came from Indonesia about 2,000 years ago.

But the first people who were like ourselves lived so long ago that even their sagas, if they had any, are forgotten. So archaeologists have neither history nor legends to help them to find out where the first 'modern men' came from.

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Fortunately, however, ancient men made tools of stone, especially flint, because this is easier to shape than other kinds. They may also have used wood and skins, but these have rotted away. Stone does not decay, and so the tools of long ago have remained when even the bones of the men who made them have disappeared without trace. Lesson2

Why, you may wonder, should spiders be our friends ? Because they destroy so many insects, and insects include some of the greatest enemies of the human race. Insects would make it impossible for us to live in the world; they would devour all our crops and kill our flocks and herds, if it were not for the protection we get from insect-eating animals. We owe a lot to the birds and beasts who eat insects but all of them put together kill only a fraction of the number destroyed by spiders. Moreover, unlike some of

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the other insect eaters, spiders never do the least harm to us or our belongings.

Spiders are not insects, as many people think, nor even nearly related to them. One can tell the difference almost at a glance for a spider always has eight legs and an insect never more than six. How many spiders are engaged in this work on our behalf ? One authority on spiders made a census of the spiders in a grass field in the south of England, and he estimated that there were more than 2,250,000 in one acre, that is something like 6,000,000 spiders of different kinds on a football pitch. Spiders are busy for at least half the year in killing insects. It is impossible to make more than the wildest guess at how many they kill, but they are hungry creatures, not content with only three meals a day. It has been estimated that the weight of all the insects destroyed by spiders in Britain in one year would be greater than the total weight of all the human beings in the country. Lesson3

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Modern alpinists try to climb mountains by a route which will give them good sport, and the more difficult it is, the more highly it is regarded. In the pioneering days, however, this was not the case at all. The early climbers were looking for the easiest way to the top because the summit was the prize they sought, especially if it had never been attained before. It is true that during their explorations they often faced difficulties and dangers of the most perilous nature, equipped in a manner which would make a modern climber shudder at the thought, but they did not go out of their way to court such excitement. They had a single aim, a solitary goal--the top!

It is hard for us to realize nowadays how difficult it was for the pioneers. Except for one or two places such as Zermatt and Chamonix, which had rapidly become popular, Alpine villages tended to be impoverished settlements cut off from civilization by the high mountains. Such inns as there were were generally dirty and flea-ridden; the food simply local cheese accompanied by bread often

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twelve months old, all washed down with coarse wine. Often a valley boasted no inn at all, and climbers

found

shelter

wherever

they

could--sometimes with the local priest (who was usually as poor as his parishioners), sometimes with shepherds or cheese-makers. Invariably the background was the same: dirt and poverty, and very uncomfortable. For men accustomed to eating seven-course dinners and sleeping between fine linen sheets at home, the change to the Alps

must have been very hard indeed. Lesson4

In the Soviet Union several cases have been reported recently of people who can read and detect colours with their fingers, and even see through solid doors and walls. One case concerns an 'eleven-year-old schoolgirl, Vera Petrova, who has normal vision but who can also perceive things with different parts of her skin, and through solid walls. This ability was first noticed by her

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father. One day she came into his office and happened to put her hands on the door of a locked safe. Suddenly she asked her father why he kept so many old newspapers locked away there, and even described the way they were done up in bundles.

Vera's curious talent was brought to the notice of a scientific research institute in the town of UIyanovsk, near where she lives, and in April she was given a series of tests by a special commission of the Ministry of Health of the Russian Federal Republic. During these tests she was able to read a newspaper through an opaque screen and, stranger still, by moving her elbow over a child's game of Lotto she was able to describe the figures and colours printed on it; and, in another instance, wearing stockings and slippers, to make out with her foot the outlines and colours of a picture hidden under a carpet. Other experiments showed that her knees and shoulders had a similar sensitivity. During all these tests Vera was blindfold; and, indeed, except when blindfold

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she lacked the ability to perceive things with her skin. It was also found that although she could perceive things with her fingers this ability ceased the moment her hands were wet. Lesson5

The gorilla is something of a paradox in the African scene. One thinks one knows him very well. For a hundred years or more he has been killed, captured, and imprisoned, in zoos. His bones have been mounted in natural history museums everywhere, and he has always exerted a strong fascination upon scientists and romantics alike. He is the stereotyped monster of the horror films and the adventure books, and an obvious (though not perhaps strictly scientific) link with our ancestral past.

Yet the fact is we know very little about gorillas. No really satisfactory photograph has ever been taken of one in a wild state, no zoologist, however intrepid, has been able to keep the animal under close and constant observation in the dark jungles

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in which he lives. Carl Akeley, the American naturalist, animals he

loved so well. But even he was unable to discover how long the gorilla lives, or how or why it dies, nor was he able to define the exact social pattern of the family groups, or indicate the final extent of their intelligence. All this and many other things remain almost as much a mystery as they were when the French explorer Du Chaillu first described the animal to the civilized world a century ago. The Abominable Snowman who haunts the imagination of climbers in the Himalayas is hardly more elusive. Lesson6

People are always talking about' the problem of youth '. If there is one—which I take leave to doubt--then it is older people who create it, not the young themselves. Let us get down to fundamentals and agree that the young are after

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led two expeditions in the

nineteen-twenties, and now lies buried among the

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all human beings--people just like their elders. There is only one difference between an old man and a young one: the young man has a glorious future before him and the old one has a splendid future behind him: and maybe that is where the rub is.

When I was a teenager, I felt that I was just young and uncertain--that I was a new boy in a huge school, and I would have been very pleased to be regarded as something so interesting as a problem. For one thing, being a problem gives you a certain identity, and that is one of the things the young are busily engaged in seeking.

I find young people exciting. They have an air of freedom, and they have not a dreary commitment to mean ambitions or love of comfort. They are not anxious social climbers, and they have no devotion to material things. All this seems to me to link them with life, and the origins of things. It's as if they were in some sense cosmic beings in violent an lovely contrast with us suburban creatures. All that is in my mind when I meet a

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young person. He may be conceited, ill- mannered, presumptuous of fatuous, but I do not turn for protection to dreary cliches about respect for elders--as if mere age were a reason for respect. I accept that we are equals, and I will argue with him, as an equal, if I think he is wrong. Lesson7

I am always amazed when I hear people saying that sport creates goodwill between the nations, and that if only the common peoples of the world could meet one another at football or cricket, they would have no inclination to meet on the battlefield. Even if one didn't know from concrete examples (the 1936 Olympic Games, for instance) that international sporting contests lead to orgies of hatred, one could deduce it from general principles.

Nearly all the sports practised nowadays are competitive. You play to win, and the game has little meaning unless you do your utmost to win. On the village green, where you pick up sides and

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no feeling of local patriotism is involved, it is possible to play simply for the fun and exercise: but as soon as the question of prestige arises, as soon as you feel that you and some larger unit will be disgraced if you lose, the most savage combative instincts are aroused. Anyone who has played even in a school football match knows this. At the international level sport is frankly mimic warfare. But the significant thing is not the behaviour of the players but the attitude of the spectators: and, behind the spectators, of the nations. who work themselves into furies over these absurd contests, and seriously believe--at any rate for short periods--that running, jumping and kicking a ball are tests of national virtue. Lesson8

Parents have to do much less for their children today than they used to do, and home has become much less of a workshop. Clothes can be bought ready made, washing can go to the laundry, food can be bought cooked, canned or

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preserved, bread is baked and delivered by the baker, milk arrives on the doorstep, meals can be had at the restaurant, the works' canteen, and the school dining-room.

It is unusual now for father to pursue his trade or other employment at home, and his children rarely, if ever, see him at his place of work. Boys are therefore seldom trained to follow their father's occupation, and in many towns they have a fairly wide choice of employment and so do girls. The young wage-earner often earns good money, and soon

acquires

feeling

economic

independence. In textile areas it has long been customary for mothers to go out to work, but this practice has become so widespread that the working mother is now a not unusual factor in a child's home life, the number of married women in employment having more than doubled in the last twenty-five years. With mother earning and his older children drawing substantial wages father is seldom the dominant figure that he still was at the beginning of the century. When mother works

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economic advantages accrue, but children lose something of great value if mother's employment prevents her from being home to greet them when they return from school. Lesson9

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

To get a full appreciation of what this means we must turn first to some recent human inventions. Everyone knows that if he shouts in the vicinity of a wall or a mountainside, an echo will come back. The further off this solid obstruction the longer time will elapse for the return of the echo. A sound made by tapping on the hull of a ship will be reflected from the sea bottom, and by measuring the time interval between the taps and the receipt of the echoes the depth of the sea at that point can

calculated.

was

born

the

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echo-sounding apparatus, now in general use in ships. Every solid object will reflect a sound, varying ac- cording to the size and nature of the object. A shoal of fish will do this. So it is a comparatively simple step from locating the sea bottom to locating a shoal of fish. With experience, and with improved apparatus, it is now possible not only to locate a shoal but to tell if it is herring, cod, or other well-known fish, by the pattern of its echo .

A few years ago it was found that certain bats emit squeaks and by receiving the echoes they could locate and steer clear of obstacles--or locate flying insects on which they feed. This echo-location in bats is often compared with radar, the principle of which is similar. Lesson10

In our new society there is a growing dislike of original, creative men. The manipulated do not understand them; the manipulators fear them. The tidy committee men regard them with horror,

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knowing that no pigeonholes can be found for them. We could do with a few original, creative men in our political life—if only to create some enthusiasm, release some energy--but where are they? We are asked to choose between various shades of the negative. The engine is falling to pieces while the joint owners of the car argue whether the footbrake or the handbrake should be applied. Notice how the cold, colourless men, without ideas and with no other passion but a craving for success, get on in this society, capturing one plum after another and taking the juice and taste out of them. Sometimes you might think the machines we worship make all the chief appointments, promoting the human beings who seem closest to them. Between mid-night and dawn, when sleep will not come and all the old wounds begin to ache, I often have a nightmare vision of a future world in which there are billions of people, all numbered and registered, with not a gleam of genius anywhere, not an original mind, a rich personality, on the whole packed globe. The

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twin ideals of our time, organization and quantity, will have won for ever. Lesson11

Alfred the Great acted as his own spy, visiting Danish camps disguised as a minstrel. In those days

wandering

minstrels

were

welcome

everywhere. They were not fighting men, and their harp was their passport. Alfred had learned many of their ballads in his youth, and could vary his programme with acrobatic tricks and simple conjuring.

While Alfred's little army slowly began to gather at Athelney, the king himself set out to penetrate the camp of Guthrum, the commander of the Danish invaders. These had settled down for the winter at Chippenham: thither Alfred went. He noticed at once that discipline was slack: the Danes had the self-confidence of conquerors, and their security precautions were casual. They lived well, on the proceeds of raids on neighbouring regions. There they collected women

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as well as food and drink, and a life of ease had made them soft.

Alfred stayed in the camp a week before he returned to Athelney. The force there assembled was trivial compared with the Danish horde. But Alfred had deduced that the Danes were no longer fit for prolonged battle : and that their commissariat had no organization, but depended on irregular raids.

So, faced with the Danish advance, Alfred did not risk open battle but harried the enemy. He was constantly on the move, drawing the Danes after him. His patrols halted the raiding parties: hunger assailed the Danish army. Now Alfred began a long series of skirmishes--and within a month the Danes had surrendered. The episode could reasonably serve as a unique epic of royal espionage! Lesson12

What characterizes almost all Hollywood pictures is their inner emptiness. This is compensated for

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by an outer impressiveness. Such impressiveness usually takes the form of truly grandiose realism. Nothing is spared to make the setting, the costumes, all of the surface details correct. These efforts help to mask the essential emptiness of the characterization,

and

the

absurdities

and

trivialities of the plots. The houses look like houses, the streets look like streets; the people look and talk like people; but they are empty of humanity, credibility, and motivation. Needless to say, the disgraceful censorship code is an important factor in predetermining the content of these pictures. But the code does not disturb the profits, nor the entertainment value of the films; it merely helps to prevent them from being credible. It isn't too heavy a burden for the industry to bear. In addition to the impressiveness of the settings, there is a use of the camera, which at times seems magical. But of what human import is all this skill, all this effort, all this energy in the production of effects, when the story, the representation of life is hollow, stupid, banal, childish ?

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Lesson13

Oxford has been ruined by the motor industry. The peace which Oxford once knew, and which a great university city should always have, has been swept ruthlessly away; and no benefactions and research endowments can make up for the change in character which the city has suffered. At six in the morning the old courts shake to the roar of buses taking the next shift to Cowley and Pressed Steel, great lorries with a double deck cargo of cars for export lumber past Magdalen and

the

University

Church.

Loads

motor-engines are hurried hither and thither and the streets are thronged with a population which has no interest in learning and knows no studies beyond

servo-systems

and

distributors,

compression ratios and camshafts.

Theoretically the marriage of an old seat of learning and tradition with a new and wealthy industry might be expected to produce some interesting children. It might have been thought

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that the culture of the university would radiate out and transform the lives of the workers. That this has not happened may be the fault of the university, for at both Oxford and Cambridge the colleges tend to

live in an era which is certainly not of the twentieth century, and upon a planet which bears little resemblance to the war-torn Earth. Wherever the fault may lie the fact remains that it is the theatre at Oxford and not at Cambridge which is on the verge of extinction, and the only fruit of the combination of industry and the rarefied atmosphere of learning is the dust in the streets, and a pathetic sense of being lost which hangs over some of the colleges. Lesson14

Some old people are oppressed by the fear of death. In the young there is a justification for this feeling. Young men who have reason to fear that they will be killed in battle may justifiably feel bitter in the thought that they have been cheated of the

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best things that life has to offer. But in an old man who has known human joys and sorrows, and has achieved whatever work it was in him to do, the fear of death is somewhat abject and ignoble. The best way to overcome it- so at least it seems to me----is to make your interests gradually wider and more impersonal, until bit by bit the walls of the ego recede, and your life becomes increasingly merged in the universal life. An individual human existence should be like a river--small at first, narrowly contained within its banks, and rushing passionately past boulders and over waterfalls. Gradually the river grows wider, the banks recede, the waters flow more quietly, and in the end, without any visible break, they become merged in the sea, and painlessly lose their individual being. The man who, in old age, can see his life in this way, will not suffer from the fear of death, since the things he cares for will continue. And it, with the decay of vitality, weariness increases, the thought of rest will be not unwelcome. I should wish to die while still at work,

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knowing that others will carry on what I can no longer do, and content in the thought that what was possible has been done. Lesson15

When anyone opens a current account at a bank, he is lending the bank money, repayment of which he may demand at any time, either in cash or by drawing a cheque in favour of another person. Primarily, the banker-customer relationship is that of debtor and creditor--who is which depending on whether the customer's account is in credit or is overdrawn. But, in addition to that basically simple concept, the bank and its customer owe a large number of obligations to one another. Many of these obligations can give rise to problems and complications but a bank customer, unlike, say, a buyer of goods, cannot complain that the law is loaded against him.

The bank must obey its customer's instructions, and not those of anyone else. When, for example, a customer first opens an account, he instructs

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the bank to debit his account only in respect of cheques drawn by himself. He gives the bank specimens of his signature, and there is a very firm rule that the bank has no right or authority to pay out a customer's money on a cheque on which its customer's signature has been forged. It makes no difference that the forgery may have been a very skilful one: the bank must recognize its customer's signature. For this reason there is no risk to the customer in the modern practice, adopted by some banks, of printing the customer's name on his cheques. If this facilitates forgery it is the bank which will lose, not the customer. Lesson16

The deepest holes of all are made for oil, and they go down to as much as 25,000 feet. But we do not need to send men down to get the oil out, as we must with other mineral deposits. The holes are only borings, less than a foot in diameter. My particular experience is largely in oil, and the

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search for oil has done more to improve deep drilling than any other mining activity. When it has been decided where we are going to drill, we put up at the surface an oil derrick. It has to be tall because it is like a giant block and tackle, and we have to lower into the ground and haul out of the ground great lengths of drill pipe which are rotated by an engine at the top and are fitted with a cutting bit at the bottom.

The geologist needs to know what rocks the drill has reached, so every so often a sample is obtained with a coring bit. It cuts a clean cylinder of rock, from which can be seen he strata the drill has been cutting through. Once we get down to the oil, it usually flows to the surface because great pressure, either from gas or water, is pushing it. This pressure must be under control, and we control it by means of the mud which we circulate down the drill pipe. We endeavour to avoid the old, romantic idea of a gusher, which wastes oil and gas. We want it to stay down the hole until we can lead it off in a controlled manner.

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Lesson17

The fact that we are not sure what 'intelligence' is, nor what is passed on, does not prevent us from finding it a very useful working concept, and placing a certain amount of reliance on tests which 'measure' it.

In an intelligence test we take a sample of an individual's ability to solve puzzles and problems of various kinds, and if we have taken a representative sample it will allow us to predict successfully the level of performance he will reach in a wide variety of occupations.

This became of particular importance when, as a result of the 1944 Education Act, secondary schooling for all became law, and grammar schools, with the exception of a small number of independent

foundation

schools,

became

available to the whole population. Since the number of grammar schools in the country could accommodate at most approximately 25 per cent of the total child population of eleven-plus, some

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kind of selection had to be made. Narrowly academic examinations and tests were felt, quite rightly, to be heavily weighted in favour of children who had had the advantage of highly-academic primary schools and academically biased homes. Intelligence tests were devised to counteract this narrow specialization, by introducing problems which

were

not

based

specifically

The

scholastically-acquired

knowledge.

intelligence test is an attempt to assess the general ability of any child to think, reason, judge, analyse and synthesize by presenting him with situations, both verbal and practical, which are within Lesson18 Two

factors

weigh

heavily

against

the

effectiveness of scientific in industry. One is the general atmosphere of secrecy in which it is carried out, the other the lack of freedom of the individual research worker. In so far as any inquiry

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his range of competence and

understanding.

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is a secret one, it naturally limits all those engaged in carrying it out from effective contact with their fellow scientists either in other countries or in universities, or even , often enough , in other departments of the same firm. The degree of secrecy naturally varies considerably. Some of the bigger firms are engaged in researches which are of such general and fundamental nature that it is a positive advantage to them not to keep them secret. Yet a great many processes depending on such research are sought for with complete secrecy until the stage at which patents can be taken out. Even more processes are never patented at all but kept as secret processes. This applies particularly to chemical industries, where chance discoveries play a much larger part than they do in physical and mechanical industries. Sometimes the secrecy goes to such an extent that the whole nature of the research cannot be mentioned. Many firms, for instance, have great difficulty in obtaining technical or scientific books from libraries because they are unwilling to have

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their names entered as having taken out such and such a book for fear the agents of other firms should be able to trace the kind of research they are likely to be undertaking. Lesson19

A gentleman is, rather than does. He is interested in nothing in a professional way. He is allowed to cultivate hobbies, even eccentricities, but must not practise a vocation. He must know how to ride and shoot and cast a fly. He should have relatives in the army and navy and at least one connection in the diplomatic service. But there are weaknesses in the English gentleman's ability to rule us today. He usually knows nothing of political economy and less about how foreign countries are governed. He does not respect learning and prefers 'sport '. The problem set for society is not the virtues of the type so much as its adequacy for its function, and here grave difficulties arise. He refuses to consider sufficiently the wants of the customer, who must buy, not the thing he desires

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but the thing the English gentleman wants to sell. He

attends

inadequately

technological

development. Disbelieving in the necessity of large-scale production in the modern world, he is passionately devoted to excessive secrecy, both in finance and method of production. He has an incurable

and

widespread

nepotism

appointment, discounting ability and relying upon a mystic entity called 'character,' which means, in a gentleman's mouth, the qualities he traditionally possesses himself. His lack of imagination and the narrowness of his social loyalties have ranged against him one of the fundamental estates of the realm. He is incapable of that imaginative realism which admits that this is a new world to which he must adjust himself and his institutions, that every privilege he formerly took as of right he can now attain only by offering proof that it is directly relevant to social welfare. Lesson20

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In the organization of industrial life the influence of the factory upon the physiological and mental state of the workers has been completely neglected. Modern industry is based on the conception of the maximum production at lowest cost, in order that an individual or a group of individuals may earn as much money as possible. It has expanded without any idea of the true nature of the human beings who run the machines, and without giving any consideration to the effects produced on the individuals and on their descendants by the artificial mode of existence imposed by the factory. The great cities have been built with no regard for us. The shape and dimensions of the skyscrapers depend entirely on the necessity of obtaining the maximum income per square foot of ground, and of offering to the tenants offices and apartments that please them. This caused the construction of gigantic buildings where too large masses of human beings are crowded together. Civilized men like such a way of living. While they enjoy the comfort and banal

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luxury of their dwelling, they do not realize that they are deprived of the necessities of life. The modern city consists of monstrous edifices and of dark, narrow streets full of petrol fumes, coal dust, and toxic gases, torn by the noise of the taxi-cabs, lorries and buses, and thronged ceaselessly by great

crowds. Obviously, it has no been planned for the good of its inhabitants. Lesson21

In the early days of the settlement of Australia, enterprising settlers unwisely introduced the European rabbit. This rabbit had no natural enemies in the Antipodes, so that it multiplied with that promiscuous abandon characteristic of rabbits. It overran a whole continent. It caused devastation by burrowing and by devouring the herbage which might have maintained millions of sheep and cattle. Scientists discovered that this particular variety of rabbit (and apparently no other animal) was susceptible to a fatal virus

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disease, myxomatosis. By infecting animals and letting them loose in the burrows, local epidemics of this disease could be created. Later it was found that there was a type of mosquito which acted as the carrier of this disease and passed it on to the rabbits. So while the rest of the world was trying to get rid of mosquitoes, Australia was encouraging this one. It effectively spread the disease all over the continent and drastically reduced the rabbit population. It later became apparent that rabbits were developing a degree of resistance to this disease, so that the rabbit population was unlikely to be completely exterminated. There were hopes, however, that the problem of the rabbit would become manageable.

Ironically, Europe, which had bequeathed the rabbit as a pest to Australia acquired this man-made disease as a pestilence. A French physician decided to get rid of the wild rabbits on his own estate and introduced myxomatosis. It did not, however, remain within the confines of his

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estate. It spread through France where wild rabbits are not generally regarded as a pest but as a sport and a useful food supply, and it spread to Britain where wild rabbits are regarded as a pest but

where

domesticated

rabbits,

equally

susceptible to the disease, are the basis of a profitable fur industry. The question became one of whether Man could control the disease he had invented. Lesson22

There has long been a superstition among mariners that porpoises will save drowning men by pushing them to the surface, or protect them from sharks by surrounding them in defensive formation. Marine Studio biologists have pointed out that, however intelligent they may be, it is probably a mistake to credit dolphins with any motive of life-saving. On the occasions when they have pushed to shore an unconscious human being they have much more likely done it out of curiosity or for sport, as in riding the bow waves of a ship.

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In 1928 some porpoises were photographed working like beavers to push ashore a waterlogged mattress. If, as has been reported, they have protected humans from sharks, it may have been because curiosity attracted them and because the scent of a possible meal attracted the sharks. Porpoises and sharks are natural enemies. It is possible that upon such an occasion a battle ensued, with the sharks being driven away or killed.

Whether it be bird, fish or beast, the porpoise is intrigued with anything that is alive. They are constantly after the turtles, the Ferdinands of marine life, who peacefully submit to all sorts of indignities. One young calf especially enjoyed raising a turtle to the surface with his snout and then shoving him across the tank like an aquaplane. Almost any day a young porpoise may be seen trying to turn a 300-pound sea turtle over by sticking his snout under the edge of his shell and pushing up for dear life. This is not easy, and may require two porpoises working together. In

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another game, as the turtle swims across the oceanarium, the first porpoise swoops down from above and butts his shell with his belly. This knocks the turtle down several feet. He no sooner recovers his equilibrium than the next porpoise comes along and hits him another crack. Eventually the turtle has been butted all the way down to the floor of the tank. He is now satisfied merely to try to stand up, but as soon as he does so a porpoise knocks him flat. The turtle at last gives up by pulling his feet under his shell and the game is over. Lesson23

It is fairly clear that the sleeping period must have some function, and because there is so much of it the function would seem to be important. Speculations about its nature have been going on for literally thousands of years, and one odd finding that makes the problem puzzling is that it looks very much as if sleeping is not simply a matter of giving the body a rest.' Rest ', in terms

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of muscle relaxation and so on, can be achieved by a brief period lying, or even sitting down. The body's

tissues

are

self-repairing

and

self-restoring to a degree, and function best when more or less continuously active. In fact a basic amount of movement occurs during sleep which is specifically concerned with preventing muscle inactivity.

If it is not a question of resting the body, then perhaps it is the brain that needs resting? This might be a plausible hypothesis were it not for two factors. First the electroencephalograph (which is simply a device for recording the electrical activity of the brain by attaching electrodes to the scalp) shows that while there is a change in the pattern of activity during sleep, there is no evidence that the total amount of activity is any less. The second factor is more interesting and more fundamental. In l960 an American psychiatrist named William Dement published experiments dealing with the recording of eye-movements during sleep. He showed that the

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average individual's sleep cycle is punctuated with peculiar bursts of eye-movements, some drifting and slow, others jerky and rapid. People woken during these periods of eye-movements generally reported that they had been dreaming. When woken at other times they reported no dreams. If one group of people were disturbed from their eye-movement sleep for several nights on end, and another group were disturbed for an equal period of time but when they were not exhibiting eye-movements, the first group began to show some personality disorders while the others seemed more or less unaffected. The implications of all this were that it was not the disturbance of sleep that mattered, but the disturbance of dreaming. Lesson24

Walking for walking' s sake may be as highly laudable and exemplary a thing as it is held to be by those who practise it. My objection to it is that it stops the brain. Many a man has professed to me

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that his brain never works so well as when he is swinging along the high road or over hill and dale This boast is not confirmed by my memory of anybody who on a Sunday morning has forced me to partake of his adventure. Experience teaches me that whatever a fellow-guest may have of power to instruct or to amuse when he is sitting in a chair, or standing on a hearth-rug, quickly leaves him when he takes one out for a walk. The ideas that come so thick and fast to him in any room, where are they now ? where that encyclopaedic knowledge which he bore so lightly ? where the kindling fancy that played like summer lightning over any topic that was started ? The man's face that was so mobile is set now; gone is the light from his fine eyes. He says that A (our host) is a thoroughly good fellow. Fifty yards further on, he adds that A is one of the best fellows he has ever met. We tramp another furlong or so and he says that Mrs A is a charming woman. Presently he adds that she is one of the most

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charming women he has ever known. We pass an inn. He reads

vapidly aloud to me: 'The King's Arms. Licensed to sell Ales and Spirits.' I foresee that during the rest of the walk he will read aloud any inscription that occurs. We pass a milestone. He points at it with his stick, and says' Uxminster. II Miles.' We turn a sharp corner at the foot of the hill. He points at the wall, and says' Drive Slowly.' .I see far ahead, on the other side of the hedge bordering the high road, a small notice-board. He sees it too. He keeps his eye on it. And in due course. 'Trespassers,' he says, 'will be Prosecuted.' Poor man !—mentally a wreck. Lesson25

How it came about that snakes manufactured poison is a mystery. Over the periods their saliva, a mild, digestive juice like our own, was converted into a poison that defies analysis even today. It was not forced upon them by the survival competition; they could have caught and lived on

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prey without using poison just as the thousands of non-poisonous snakes still do. Poison to a snake is merely a luxury; it enables it to get its food with very little effort, no more effort than one bite. And why only snakes ? Cats, for instance, would be greatly helped; no running rights with large, fierce rats or tussles with grown rabbits- just a bite and no more effort needed. In fact it would be an assistance to all the carnivorae--though it would be a two-edged weapon -When they fought each other. But, of the vertebrates, unpredictable Nature selected only snakes (and one lizard). One wonders also why Nature, with some snakes concocted poison of such extreme potency. In the conversion of saliva into poison one might suppose that a fixed process took place. It did not; some snakes manufactured a poison different in every respect from that of others, as different as arsenic is from strychnine, and having different effects. One poison acts on the nerves, the other on the blood.

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