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Lesson54 Instinct or cleverness？
We have been brought up to fear insects。 We regard them as unnecessary creatures that do more harm than good。 Man continually wages war on item； for they contaminate his food； carry diseases； or devour his crops。 They sting or bite without provocation； they fly uninvited into our rooms on summer nights； or beat against our lighted windows。 We live in dread not only of unpleasant insects like spiders or wasps； but of quite harmless ones like moths。 Reading about them increases our understanding with out dispelling our fears。 Knowing that the industrious ant lives in a highly
organized society does nothing to prevent us from being filled with revulsion when we find hordes of them crawling over a carefully prepared picnic lunch。 No matter how much we like honey； or how much we have read about the uncanny sense of direction which bees possess； we have a horror of being stung。 Most of our fears are unreasonable； but they are impossible to erase。 At the same time； however； insects are strangely fascinaing。 We enjoy reading about them； especially when we find that； like the praying mantis； they lead perfectly horrible lives。 We enjoy staring at them entranced as they go about their business； unaware （we hope） of our presence。 Who has not stood in awe at the sight of a spider pouncing on a fly； or a column of ants triumphantly bearing home an enormous dead beetle ？
Last summer I spent days in the garden watching thousands of ants crawling up the trunk of my prize peach tree。 The tree has grown against a warm wall on a sheltered side of the house。 I am especially proud of it； not only because it has survived several severe winters； but because it occasionally produces luscious peaches。 During the summer； I noticed that the leaves of the tree were beginning to wither。 Clusters of tiny insects called aphides were to be found on the underside of the leaves。 They were visited by a laop colony of ants which obtained a sort of honey from them。 I immediately embarked on an experiment which； even though it failed to get rid of the ants； kept me fascinated for twenty…four hours。 I bound the base of the tree with sticky tape ； making it impossible for the ants to reach the aphides。 The tape was so sticky that they did not dare to cross it。 For a long time； I watched them scurrying around the base of the tree in bewilderment。 I even went out at midnight with a torch and noted with satisfaction （and surprise） that the ants were still swarming around the sticky tape without being able to do anything about it。 I got up early next morning hoping to find that the ants had given up in despair。 Instead； I saw that they had discovered a new route。 They were climbing up the wall of the house and then on to the leaves of
the tree。 I realized sadly that I had been completely defeated by their ingenuity。 The ants had been quick to find an answer to my thoroughly unscientific methods！
Lesson55 From the earth： greatings
Radio astronomy has greatly increased our understanding of the universe。 Radio telescopes have one big advantage over conventional telescopes in that they can operate in all weather conditions and can pick up signals coming from very distant stars。 These signals are produced by colliding stars or nuclear reactions in outer space。 The most powerful signals that have been received have been emitted by what seem to be truly colossal stars which scientists have named 'quasars'。
A better understanding of these phenomena may completely alter our conception of the nature of the universe。 The radio telescope at Jodrell Bank in England was for many years the largest in the world。 A new telescope； over twice the size； was recently built at Sugar Grove in West Virginia。 Astronomers no longer regard as fanciful the idea that they may one day pick up signals which have been sent by intelligent beings on other worlds。 This possibility gives rise to interesting speculations。 Highly advanced civilizations may have existed on other planets long before intelligent forms of life evolved on the earth。 Conversely； intelligent being which are just beginning to develop on remote worlds may be ready to pick up our signals in thousands of years' time； or when life on earth has become extinct。 Such speculations no longer belong to the realm of science fiction； for astronomers are now exploring the chances of communicating with living creatures （if they exist） on distant planets。 This undertaking which has been named Project Ozma was begun in 1960； but it may take a great many years before results are obtained。
Aware of the fact that it would be impossible to wait thousands or millions of years to receive an answer from a distant planet； scientists engaged in Project Ozma are concentrating their attention on stars which are relatively close。 One of the most likely stars is Tau Ceti which is eleven light years away。 If signals from the earth were received by intelligent creatures on a planet circling this
star； we would have to wait twenty…two years for an answer。 The Green Bank telescope in West Virginia has been specially designed to distinguish between random signals and signals which might be in code。 Even if contact were eventually established； astronomers would not be able to rely on language to communicate with other beings。 They would use mathematics as this is the
only truly universal language。 Numbers have the same value anywhere。 For this reason； intelligent creatures in any part of the universe would be able to understand a simple arithmetical sequence。 They would be able to reply to our signals using similar methods。 The next step would be to try to develop means for sending television pictures。 A single picture would tell us more than thousands of words。 In an age when anything seems to be possible； it would be narrow…minded in the extreme to ridicule these attempts to find out if there is life in other parts of the universe。
Lesson56 The river beside our farm
The river which forms the eastern boundary of our farm has always played an important part in our lives。 Without it we could not make a living。 There is only enough spring water to supply the needs of the house； so we have to pump from the river for farm use。 We tell the river all our secrets。 We know instinctively； just as beekeepers with their bees； that misfortune might overtake us if the important events of our lives were not related to it。
We have special river birthday parties in the summer。 Sometimes we go up…stream to a favourite backwater； some… times we have our party at the boathouse； which a predecessor of ours at the farm built in the meadow hard by the deepest pool for swimming and diving。 In a heat…wave we choose a midnight birthday party and that is the most exciting of all。 We welcome the seasons by the river… side； crowning the youngest girl with flowers in the spring； holding a summer festival on Midsummer Eve； giving thanks for the harvest in the autumn； and throwing a holly wreath into the current in the winter。 After a long period of rain the river may overflow its banks。 This is a rare occurrence as our climate seldom god to extremes。 We are lucky in that only the lower fields； which make up a very small proportion of our farm； a