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to find that the machine still refused
to work after I had reassembled it； for the simple reason that I was left with several curiously shaped bits of metal which did not seem to fit anywhere。 I gave up in despair。 The weeks passed and the grass grew。 When my wife nagged me to do something about it； I told her that either I would have to buy a new mower or let the grass grow。 Needless to say our house is now surrounded by a jungle。 Buried somewhere in deep grass there is a rusting lawn…mower which I have promised to repair one day。
Lesson47 Through the earth鈥檚 crust
Satellites orbiting round the earth have provided scientists with a vast amount of information about conditions in outer space。 By comparison； relatively little is known about the internal structure of the earth。 It has proved easier to go up than to go down。 The deepest hole ever to be
bored on land went down 25；340 feet considerably less than the height of Mount Everest。 Drilling a hole under the sea has proved to be even more difficult。 The deepest hole bored under sea has been about 20；000 feet。 Until recently； scientists have been unable to devise a drill which would be capable of cutting through hard rock at great depths。 This problem has now been solved。 Scientists have developed a method which sounds surprisingly simple。 A new drill which is being tested at Leona Valley Ranch in Texas is driven by a turbine engine which is propelled by liquid mud pumped into it from the surface。 As the diamond tip of the drill revolves； it is lubricated by mud。 Scientists have been amazed to find that it can cut through the hardest rock with great ease。 The drill has been designed to bore through the earth to a depth of 35；000 feet。 It will enable scientists to obtain samples of the mysterious layer which lies immediately below the earth's crust。 This layer is known as the Mohorovicic Discontinuity； but is commonly referred to as 'the Moho'。
Before it is possible to drill this deep hole； scientists will have to overcome a number of problems。 Geological tests will be carried out to find the point at which the earth's crust is thinnest。 The three possible sites which are being considered are all at sea： two in the Atlantic Ocean and one in the Pacific。 Once they have determinded on a site； they will have to erect a drilling vessel which will
not be swept away by ocean currents。 The vessel will consist of an immense platform which will rise to 70 feet above the water。 It will be supported by six hollow columns which will descend to a depth of 60 feet below the ocean surface where they will be fixed to a huge float。 A tall steel tower rising to a height of nearly 200 feet will rest on the platform。 The drill will be stored in the tower
and will have to be lowered through about 15；000 feet of water before operations can begin。 Within the tower； there will be a laboratory； living accommodation and a helicopter landing station。 Keeping the platform in position at sea will give rise to further problems。 To do this； scientists will have to devise methods using radar and underwater television。 If； during the operations the drill has to be withdrawn； it must be possible to re…insert it。 Great care will therefore have to be taken to keep the platform steady and make it strong enough to withstand hurricanes。 If the project is successful； scientists will not only learn a great deal about the earth； but possibly about the nature of the universe itself。
Lesson48 The silent village
In this much…travelled world； there are still thousands of places which are inaccessible to tourists。 We always assume that villagers in remote places are friendly and hospitable。 But people who are cut off not only from foreign tourists； but even from their own countrymen can be hostile to travellers。 Visits to really remote villages are seldom enjoyableas my wife and I discovered during a tour through the Balkans。
We had spent several days in a small town and visited a number of old churches in the vicinity。 These attracted many visitors for they were not only of great architectural interest； but contained a
large number of beautifully preserved frescoes as well。 On the day before our departure； several bus loads of tourists descended on the town。 This was more than we could bear； so we decided to spend our last day exploring the countryside。 Taking a path which led out of the town； we crossed a few fields until we came to a dense wood。 We expected the path to end abruptly； but we found that it traced its way through the trees。 We tramped through the wood for over two hours until we arrived at a deep stream。 We could see that the path continued on the other side； but we had no idea how we could get across the stream。 Suddenly my wife spotted a boat moored to the bank。 In it there was a boatman fast asleep。 We gently woke him up and asked him to ferry us to the other side。 Though he was reluctant to do so at first； we eventually persuaded him to take us。 The path led to a tiny village perched on the steep sides of a mountain。 The place consisted of a straggling unmade road which was lined on either side by small houses。 Even under a clear blue sky； the village looked forbidding； as all the houses were built of grey mud bricks。 The village seemed deserted； the only sign of life being an ugly…looking black goat tied to a tree on a short length of
rope in a field nearby。 Sitting down on a dilapidated wooden fence near the field； we opened a couple of tins of sardines and had a picnic lunch。 All at once； I noticed that my wife seemed to be filled with alarm。 Looking up I saw that we were surrounded by children in rags who were looking at us silently as we ate。 We offered them food and spoke to them kindly； but they remained motionless。 I concluded that they were simply shy of strangers。 When we later walked down the main street of the village； we were followed by a silent procession of children。 The village which had seemed deserted； immediately came to life。 Faces appeared at windows。 Men in shirt sleeves stood outside their houses and glared at us。 Old women in black shawls peered at us from door…ways。 The most frightening thing of all was that not a sound could be heard。 There was no doubt that we were unwelcome visitors。 We needed no further warning。 Turning back down the main street； we quickened our pace and made our way rapidly towards the stream where we hoped the boatman was waiting。
Lesson49 The Ideal Servant
It is a good thing my aunt Harriet died years ago。 If she were alive today she would not be able to air her views on her favourite topic of conversation： domestic servants。 Aunt Harriet lived in that
leisurely age when servants were employed to do housework。 She had a huge； rambling country house called 'The Gables'。 She was sentimentally attached to this house； for even though it was far
too big for her needs； she persisted in living there long after her husband's death。 Before she grew old； aunt Harriet used to entertain lavishly。 I often visited The Gables when I was a boy。 No matter
how many guests were present； the great house was always immaculate。 The parquet floors shone like mirrors； highly polished silver was displayed in gleaming glass cabinets； even my uncle's huge